Bicycle controller

ABSTRACT

A bicycle controller controls a motor in accordance with the riding environment of a bicycle. The bicycle controller includes an electronic control unit that is configured to control a motor, which assists pedaling of a bicycle in accordance with a manual driving force. The electronic control unit is further configured to change a response speed of the motor with respect to a change in the manual driving force in accordance with an inclination angle of the bicycle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No.2016-149752, filed on Jul. 29, 2016, and Japanese Patent Application No.2017-129061, filed on Jun. 30, 2017. The entire disclosures of JapanesePatent Application No. 2016-149752 and Japanese Patent Application No.2017-129061 are hereby incorporated herein by reference.

BACKGROUND Field of the Invention

The present invention generally relates to a bicycle controller.

Background Information

Japanese Patent No. 5575968 (Patent document 1) discloses a bicyclecontroller that changes the speed at which an output of a motor respondsto a change in manual driving force. In a case in which the manualdriving force decreases, the bicycle controller changes the responsespeed of the motor output in accordance with a crank rotation speed.

SUMMARY

There is a demand for a bicycle controller that is configured to controlthe motor in a suitable manner even if the riding environment of thebicycle changes. It is an object of the present invention to provide abicycle controller that is configured to control a motor in accordancewith the riding environment of a bicycle.

In accordance with a first aspect of the present invention, a bicyclecontroller includes an electronic control unit configured to control amotor, which assists propulsion of a bicycle, in accordance with amanual driving force. The electronic control unit is further configuredto change a response speed of the motor with respect to a change in themanual driving force in accordance with an inclination angle of thebicycle.

The inclination angle of the bicycle reflects the gradient of a roadsurface. The road surface is one example of a riding environment of thebicycle. With the bicycle controller according to the first aspect, theresponse speed of the motor with respect to a change in the manualdriving force is changed in accordance with the inclination angle of thebicycle. This allows the motor to be controlled in accordance with theriding environment of the bicycle.

In accordance with a second aspect of the present invention, the bicyclecontroller according to the first aspect is configured so that theelectronic control unit is further configured to change the responsespeed in a case in which the manual driving force decreases. The manualdriving force is maximal in a case in which a rotational angle of acrank reaches an intermediate angle between the top dead center and thebottom dead center of a crank and decreases as the rotational angle ofthe crank approaches the top dead center or the bottom dead center froman intermediate angle. With the bicycle controller according to thesecond aspect, the response speed is changed in a case in which themanual driving force decreases. Thus, as the rotational angle of thecrank approaches the top dead center or the bottom dead center from anintermediate angle, the motor can be controlled in accordance with theriding environment of the bicycle.

In accordance with a third aspect of the present invention, the bicyclecontroller according to the second aspect is configured so that theelectronic control unit is further configured to decrease the responsespeed in a case in which the inclination angle of the bicycle increaseson an uphill. With the bicycle controller according to the third aspect,the response speed of the motor is decreased in a case in which theinclination angle of the bicycle increases on an uphill. Thus, adecrease in the output of the motor is limited as the rotational angleof the crank shifts from the intermediate angle to the top dead centeror the bottom dead center. This assists the propulsion of the bicycle ina manner suitable for an uphill where the load on the rider is high.

In accordance with a fourth aspect of the present invention, the bicyclecontroller according to the second or third aspect is configured so thatthe electronic control unit is further configured to increase theresponse speed in a case in which the inclination angle of the bicycleincreases on a downhill. With the bicycle controller according to thefourth aspect, in a case in which the inclination angle of the bicycleincreases on a downhill, the motor output can easily be decreased if themanual driving force decreases. This assists the propulsion of thebicycle in a manner suitable for a downhill where the load on the rideris low.

In accordance with a fifth aspect of the present invention, the bicyclecontroller according to any one of the first to fourth aspects isconfigured so that the electronic control unit is further configured tochange the response speed in a case in which the manual driving forceincreases. With the bicycle controller according to the fifth aspect,the response speed is changed in a case in which the manual drivingforce increases. This allows the motor to be controlled in accordancewith the riding environment of the bicycle in a case in which therotational angle of the crank shifts from the top dead center or thebottom dead center to an intermediate angle.

In accordance with a sixth aspect of the present invention, the bicyclecontroller according to the fifth aspect is configured so that theelectronic control unit is further configured to increase the responsespeed in a case in which the inclination angle of the bicycle increaseson an uphill. With the bicycle controller according to the sixth aspect,the response speed is increased in a case in which the inclination angleof the bicycle increases on an uphill. Thus, the output of the motorquickly increases as the rotational angle of the crank shifts from thetop dead center or the bottom dead center to an intermediate angle. Thisassists the propulsion of the bicycle in a manner suitable for adownhill where the load on the rider is high.

In accordance with a seventh aspect of the present invention, thebicycle controller according to the fifth or sixth aspect is configuredso that the electronic control unit is further configured to decreasethe response speed in a case in which the inclination angle of thebicycle increases on a downhill. With the bicycle controller accordingto the seventh aspect, the response speed in decreased in a case inwhich the inclination angle of the bicycle increases on a downhill.

In accordance with an eighth aspect of the present invention, thebicycle controller according to any one of the first to seventh aspectsis configured so that the electronic control unit is further configuredto change the response speed in a stepped manner in accordance with theinclination angle of the bicycle. With the bicycle controller accordingto the eighth aspect, the processing for changing the response speed canbe simplified compared to a case that continuously changes the responsespeed in accordance with the inclination angle of the bicycle.

In accordance with a ninth aspect of the present invention, the bicyclecontroller according to any one of the first to eighth aspects isconfigured so that the electronic control unit is further configured tofix the response speed in a case in which the inclination angle of thebicycle on an uphill is greater than or equal to a first angle. With thebicycle controller according to the ninth aspect, the response speed isfixed in a case in which the inclination angle of the bicycle on anuphill is greater than or equal to a first angle. This reduces the loadon the processing for changing the response speed in accordance with theinclination angle of the bicycle.

In accordance with a tenth aspect of the present invention, the bicyclecontroller according to any one of the first to ninth aspect isconfigured so that the electronic control unit is further configured tofix the response speed in a case in which the inclination angle of thebicycle on a downhill is greater than or equal to a second angle. Withthe bicycle controller according to the tenth aspect, the load isreduced on the processing for changing the response speed in accordancewith the inclination angle of the bicycle becomes too large.

In accordance with an eleventh aspect of the present invention, thebicycle controller according to any one of the first to tenth aspects isconfigured so that the electronic control unit is further configured toset the response speed for a case in which a vehicle speed of thebicycle is less than or equal to a first speed to be different from theresponse speed for a case in which the vehicle speed of the bicycleexceeds the first speed. With the bicycle controller according to theeleventh aspect, the propulsion of the bicycle is assisted in a mannersuitable for the vehicle speed in a case in which the vehicle speed isless than or equal to a first speed and a case in which the vehiclespeed exceeds the first speed.

In accordance with a twelfth aspect of the present invention, thebicycle controller according to any one of the first to eleventh aspectis configured so that the electronic control unit is further configuredto change the response speed in accordance with a change in theinclination angle of the bicycle. With the bicycle controller accordingto the twelfth aspect, the propulsion of the bicycle is assisted in amanner suitable in a case in which the inclination angle of the roadchanges.

In accordance with a thirteenth aspect of the present invention, thebicycle controller according to the twelfth aspect is configured so thatupon determining an increasing speed of the inclination angle of thebicycle increases on an uphill, the electronic control unit is furtherconfigured to increase the response speed in a case in which the manualdriving force increases. With the bicycle controller according to thethirteenth aspect, the output of the motor can be controlled inaccordance with the propelling state of the rider on an uphill on whichthe inclination angle gradually increases.

In accordance with a fourteenth aspect of the present invention, thebicycle controller according to the twelfth or thirteenth aspect isconfigured so that upon determining the inclination angle of the bicyclechanges during a first period from an angle corresponding to an uphillto a third angle or greater on a downhill, the electronic control unitis further configured to decreases the response speed in a case in whichthe manual driving force increases. With the bicycle controlleraccording to the fourteenth aspect, the propulsion of the bicycle can beassisted in a manner suitable for the road surface in a case in whichthe road changes from an uphill to a downhill that is greater than orequal to the third angle.

In accordance with a fifteenth aspect of the present invention, thebicycle controller according to any one of the first to fourteenthaspect is configured so that the electronic control unit is furtherconfigured to change the response speed in accordance with a rotationspeed of a crank of the bicycle. With the bicycle controller accordingto the fifteenth aspect, the motor output can be controlled inaccordance with the propelling state of the rider.

In accordance with a sixteenth aspect of the present invention, thebicycle controller according to the fifteenth aspect is configured sothat the electronic control unit is configured to control the motor in afirst mode that decreases the response speed as the rotation speed ofthe crank increases. With the bicycle controller according to thesixteenth aspect, in the first mode, the motor output is easilydecreased if the manual driving force decreases in a case in which thecrank rotation speed is low while the bicycle is traveling. This allowsthe rider to easily control the bicycle. Further, wheelspin isrestricted as the bicycle starts to travel. The motor control in thefirst mode allows the rider to smoothly ride the bicycle off-roadespecially on a bumpy surface.

In accordance with a seventeenth aspect of the present invention, thebicycle controller according to the sixteenth aspect is configured sothat the electronic control unit is further configured to fix theresponse speed in the first mode in a case in which the rotation speedof the crank is higher than or equal to a first speed. With the bicyclecontroller according to the seventeenth aspect, in the first mode, theresponse speed is fixed if the rotation speed of the crank is higherthan or equal to the first speed. This reduces the load on theprocessing for changing the response speed in accordance with therotation speed of the crank.

In accordance with an eighteenth aspect of the present invention, thebicycle controller according to the fifteenth aspect is configured sothat the electronic control unit is configured to control the motor in asecond mode that increases the response speed as the rotation speed ofthe crank increases. With the bicycle controller according to theeighteenth aspect, in the second mode, a decrease in the motor output islimited if the manual driving force decreases in a state in which therotation speed of the crank is low while the bicycle is traveling. Thisreduces interruptions in the assistance provided by the motor. The motorcontrol in the second mode allows the rider to smoothly ride the bicycleon-road especially on an even surface.

In accordance with a nineteenth aspect of the present invention, thebicycle controller according to the eighteenth aspect is configured sothat the electronic control unit is further configured to fix theresponse speed in the second mode in a case in which the rotation speedof the crank is higher than or equal to a second speed. With the bicyclecontroller according to the nineteenth aspect, in the second mode, theresponse speed is fixed in a case in which the rotation speed of thecrank is higher than or equal to the second speed. This reduces the loadon the processing for changing the response speed in accordance with therotation speed of the crank.

In accordance with a twentieth aspect of the present invention, thebicycle controller according to the sixteenth or seventeenth aspect isconfigured so that the electronic control unit is configured to controlthe motor in a second mode that increases the response speed as therotation speed of the crank increases. With the bicycle controlleraccording to the twentieth aspect, a decrease in the motor output islimited if the manual driving force decreases in a state in which therotation speed of the crank is low while the bicycle is traveling. Thisreduces interruptions in the assistance provided by the motor. The motorcontrol in the second mode allows the rider to smoothly ride the bicycleespecially on-road

In accordance with a twenty-first aspect of the present invention, thebicycle controller according to the twentieth aspect is configured sothat the electronic control unit is further configured to fix theresponse speed in the second mode in a case in which the rotation speedof the crank is higher than or equal to a second speed. With the bicyclecontroller according to the twenty-first aspect, in the second mode, theresponse speed is fixed in a case in which the rotation speed of thecrank is higher than or equal to the second speed. This reduces the loadon the processing for changing the response speed in accordance with therotation speed of the crank.

In accordance with a twenty-second aspect of the present invention, thebicycle controller according to the twentieth or twenty-first aspect isconfigured so that the electronic control unit is configured to switchbetween the first mode and the second mode in accordance with operationof an operation unit that is configured to communicate with theelectronic control unit. With the bicycle controller according to thetwenty-second aspect, the rider can decide to switch between the firstmode and the second mode.

In accordance with a twenty-third aspect of the present invention, thebicycle controller according to any one of the first to twenty-secondaspect is configured so that the electronic control unit is furtherconfigured to change the response speed with a low-pass filter. With thebicycle controller according to the twenty-third aspect, the responsespeed is changed with the low-pass filter. This allows the responsespeed to be changed through simple processing.

In accordance with a twenty-fourth aspect of the present invention, abicycle controller includes an electronic control unit configured tocontrol a motor, which assists propulsion of a bicycle, in accordancewith operation of an operation unit provided on the bicycle. Theelectronic control unit is further configured to change an increasingspeed of an output torque of the motor in accordance with at least oneof an inclination angle of the bicycle and a change amount of theinclination angle of the bicycle. With the bicycle controller accordingto the twenty-fourth aspect, in a case in which the motor is controlledin accordance with operation of the operation unit, the motor can becontrolled so that the increasing speed of the output torque of themotor is suitable for at least one of the inclination angle of thebicycle and the change amount of the inclination angle of the bicycle.

In accordance with a twenty-fifth aspect of the present invention, thebicycle controller according to the twenty-fourth aspect is configuredso that the electronic control unit is further configured to increasethe increasing speed of the output torque of the motor in a case inwhich the inclination angle of the bicycle increases on an uphill. Withthe bicycle controller according to the twenty-fifth aspect, the outputtorque of the motor is quickly increased in a case in which theinclination angle of the bicycle increases on an uphill.

In accordance with a twenty-sixth aspect of the present invention, thebicycle controller according to the twenty-fourth or twenty-fifth aspectis configured so that the electronic control unit is further configuredto decrease the increasing speed of the output torque of the motor in acase in which the inclination angle of the bicycle increases on adownhill. With the bicycle controller according to the twenty-sixthaspect, increases in the output torque of the motor are limited in acase in which the inclination angle of the bicycle increases on adownhill.

In accordance with a twenty-seventh aspect of the present invention, thebicycle controller according to any one of the twenty-fourth totwenty-sixth aspect is configured so that the electronic control unit isfurther configured to increase the increasing speed of the output torqueof the motor in a case in which an increasing speed of the inclinationangle of the bicycle increases on an uphill. With the bicycle controlleraccording to the twenty-seventh aspect, the output torque of the motorcan be quickly increased in a case in which the bicycle travels on anuphill road of which the gradient gradually increases.

In accordance with a twenty-eighth aspect of the present invention, thebicycle controller according to any one of the twenty-fourth totwenty-seventh aspect is configured so that the electronic control unitis further configured to decrease the increasing speed of the outputtorque of the motor in a case in which an increasing speed of theinclination angle of the bicycle increases on a downhill. With thebicycle controller according to the twenty-eighth aspect, increases inthe output torque of the motor are limited in a case in which thebicycle travels on a downhill road of which the gradient graduallyincreases.

In accordance with a twenty-ninth aspect of the present invention, abicycle controller includes an electronic control unit configured tocontrol a motor that assists propulsion of a bicycle. The electroniccontrol unit is further configured to control an output torque of themotor to be less than or equal to a predetermined torque. Thepredetermined torque is changed in accordance with an inclination angleof the bicycle. With the bicycle controller according to thetwenty-ninth aspect, the motor is controlled so that the output torqueis suitable for the inclination angle.

In accordance with a thirtieth aspect of the present invention, thebicycle controller according to the twenty-ninth aspect is configured sothat the predetermined torque includes a first torque. The electroniccontrol unit is further configured to control the motor in accordancewith manual driving force. The electronic control unit is furtherconfigured to control the output torque of the motor to be less than orequal to the first torque in a case in which the electronic control unitcontrols the motor in accordance with manual driving force. The firsttorque is changed in accordance with the inclination angle of thebicycle. With the bicycle controller according to the thirtieth aspect,the motor is controlled so that the output torque is less than or equalto the first torque and suitable for the inclination angle.

In accordance with a thirty-first aspect of the present invention, thebicycle controller according to the thirtieth aspect is configured sothat the electronic control unit is further configured to increase thefirst torque in a case in which the inclination angle of the bicycleincreases on an uphill. With the bicycle controller according to thethirty-first aspect, the electronic control unit increases the firsttorque in a case in which the inclination angle of the bicycle increaseson an uphill.

In accordance with a thirty-second aspect of the present invention, thebicycle controller according to any one of the twenty-ninth tothirty-first aspects is configured so that the predetermined torqueincludes a second torque. The electronic control unit is furtherconfigured to control the motor in accordance with operation of anoperation unit provided on the bicycle. The electronic control unit isfurther configured to control the output torque of the motor to be lessthan or equal to the second torque in a case in which the electroniccontrol unit controls the motor in accordance with the operation of theoperation unit. The second torque is changed in accordance with theinclination angle of the bicycle. With the bicycle controller accordingto the thirty-second aspect, in a case in which the motor is controlledin accordance with the operation of the operation unit, the motor iscontrolled so that the output torque is less than or equal to the secondtorque and suitable for the inclination angle.

In accordance with a thirty-third aspect of the present invention, thebicycle controller according to the thirty-second aspect is configuredso that the electronic control unit is further configured to increasethe second torque in a case in which the inclination angle of thebicycle increases on an uphill. With the bicycle controller according tothe thirty-third aspect, the output torque of the motor can be increasedin a case in which the inclination angle of the bicycle increases on anuphill.

In accordance with a thirty-fourth aspect of the present invention, thebicycle controller according to any one of the first to thirty-thirdaspects further includes an inclination detector that detects theinclination angle of the bicycle. With the bicycle controller accordingto the thirty-fourth aspect, the inclination detector can detect theinclination angle of the bicycle.

In accordance with a thirty-fifth aspect of the present invention, thebicycle controller according to any one of the first to twenty-third,thirtieth, and thirty-first aspects is configured so that the electroniccontrol unit is further configured to compute the inclination anglebased on the manual driving force and a rotation speed of a crank of thebicycle. With the bicycle controller according to the thirty-fifthaspect, the electronic control unit computes the inclination angle basedon the manual driving force and the rotation speed of the crank. Thus,in addition to a sensor that detects the manual driving force and thesensor that detects the crank rotation speed, there is no need for aseparate sensor that detects the inclination angle.

In accordance with a thirty-sixth aspect of the present invention, abicycle controller includes an electronic control unit configured tocontrol a motor, which assists propulsion of a bicycle, in accordancewith a manual driving force. The electronic control unit is furtherconfigured to set a response speed of the motor with respect to a changein the manual driving force for a case in which a vehicle speed of thebicycle is less than or equal to a first speed to be different from theresponse speed for a case in which the vehicle speed of the bicycleexceeds the first speed. With the bicycle controller according to thethirty-sixth aspect, the motor can be controlled with a response speedsuitable for a case in which the vehicle speed of the bicycle is lessthan or equal to a first speed and for a case in which the vehicle speedof the bicycle exceeds the first speed.

In accordance with a thirty-seventh aspect of the present invention, thebicycle controller according to the thirty-sixth aspect is configured sothat the electronic control unit is further configured to set theresponse speed for the case in which the vehicle speed of the bicycle isless than or equal to the first speed to be higher than the responsespeed for the case in which the vehicle speed of the bicycle exceeds thefirst speed. With the bicycle controller according to the thirty-seventhaspect, the output of the motor can be quickly increased if the outputof the motor is increased in a case in which the vehicle speed of thebicycle is less than or equal to the first speed.

In accordance with a thirty-eighth aspect of the present invention, abicycle controller includes an electronic control unit configured tocontrol a motor, which assists propulsion of a bicycle, in accordancewith a manual driving force. The electronic control unit is furtherconfigured to set a response speed of the motor with respect to a changein the manual driving force input to the bicycle for a case within apredetermined period from a time at which the bicycle starts to travelto be different from the response speed for a case in which thepredetermined period has elapsed. With the bicycle controller accordingto the thirty-eighth aspect, the motor can be controlled with a responsespeed suitable for a case within a predetermined period from the time atwhich the bicycle starts to travel and for a case in which thepredetermined period has elapsed.

In accordance with a thirty-ninth aspect of the present invention, thebicycle controller according to the thirty-eighth aspect is configuredso that the electronic control unit is further configured to set theresponse speed for the case within the predetermined period from thetime at which the bicycle starts to travel to be higher than theresponse speed for the case in which the predetermined period haselapsed. With the bicycle controller according to the thirty-ninthaspect, the output of the motor can be quickly increased if the outputof the motor is increased within a predetermined period from the time atwhich the bicycle starts to travel.

The bicycle controller according to the present invention is configuredto control a motor in accordance with the riding environment of abicycle.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring now to the attached drawings which form a part of thisoriginal disclosure.

FIG. 1 is a block diagram in accordance with an electrical configurationof a bicycle including a bicycle controller in accordance with a firstembodiment.

FIG. 2 is a flowchart of a motor control executed by an electroniccontrol unit shown in FIG. 1.

FIG. 3 is a graph in accordance with the relationship of a time constantand a crank rotation speed with respect to an inclination angle in afirst mode set by the electronic control unit shown in FIG. 1.

FIG. 4 is a graph in accordance with the relationship of the timeconstant and the crank rotation speed with respect to the inclinationangle in a second mode set by the electronic control unit shown in FIG.1.

FIG. 5 is a series of timing charts in accordance with one example ofthe motor control in the first mode.

FIG. 6 is a series of timing charts in accordance with one example ofthe motor control in the second mode.

FIG. 7 is a flowchart of a motor control executed by the electroniccontrol unit in accordance with a second embodiment.

FIG. 8 is a series of timing charts in accordance with one example ofthe motor control in a first mode of the second embodiment.

FIG. 9 is a series of timing charts in accordance with one example ofthe motor control in a second mode of the second embodiment.

FIG. 10 is a first flowchart of a motor control executed by theelectronic control unit in accordance with a third embodiment.

FIG. 11 is a second flowchart of the motor control executed by theelectronic control unit in accordance with the third embodiment.

FIG. 12 is a graph in accordance with the relationship of a first torqueand the rotation speed of a crank set by the electronic control unit inaccordance with a fourth embodiment.

FIG. 13 is a flowchart of a motor control executed by the electroniccontrol unit in accordance with the fourth embodiment.

FIG. 14 is a first flowchart of a motor control executed by theelectronic control unit in accordance with a fifth embodiment.

FIG. 15 is a second flowchart of the motor control executed by theelectronic control unit in accordance with the fifth embodiment.

FIG. 16 is a timing chart in accordance with one example of the motorcontrol in accordance with a sixth embodiment.

FIG. 17 is a flowchart of a motor control executed by the electroniccontrol unit in accordance with a seventh embodiment.

FIG. 18 is a flowchart of a motor control executed by the electroniccontrol unit in accordance with an eighth embodiment.

FIG. 19 is a flowchart in accordance with a first modified example ofthe motor control.

FIG. 20 is a flowchart in accordance with a second modified example ofthe motor control.

FIG. 21 is a flowchart in accordance with a third modified example ofthe motor control.

FIG. 22 is a flowchart in accordance with a fourth modified example ofthe motor control.

FIG. 23 is a flowchart in accordance with a fifth modified example ofthe motor control.

FIG. 24 is a flowchart in accordance with a sixth modified example ofthe motor control.

FIG. 25 is a flowchart in accordance with a seventh modified example ofthe motor control.

DETAILED DESCRIPTION OF EMBODIMENTS

Selected embodiments will now be explained with reference to thedrawings. It will be apparent to those skilled in the bicycle field fromthis disclosure that the following descriptions of the embodiments areprovided for illustration only and not for the purpose of limiting theinvention as defined by the appended claims and their equivalents.

A bicycle 10 including one embodiment of a bicycle controller will nowbe described with reference to FIG. 1. The bicycle 10 includes a drivemechanism 12, an operation unit 14, a battery 16, an assist device 18and a bicycle controller 30. The bicycle 10 is, for example, a mountainbike but can be a road bike or a city bike.

The drive mechanism 12 includes a crank 12A and a pair of pedals 12D.The crank 12A includes a crankshaft 12B and a pair of crank arms 12C.The drive mechanism 12 transmits a manual driving force, which isapplied to the pedals 12D by a rider to rotate a rear wheel (not shown).The drive mechanism 12 is configured to transmit the rotation of thecrank through, for example, a chain, a belt or a shaft (none shown). Thedrive mechanism 12 includes a front rotating body (not shown) that isconnected to the crankshaft 12B by a one-way clutch (not shown). Theone-way clutch is configured to rotate the front rotating body forwardin a case in which the crank 12A is rotated forward. The one-way clutchis configured to restrict rearward rotation of the front rotating bodyin a case in which the crank 12A is rotated rearward. The front rotatingbody includes a sprocket, a pulley, or a bevel gear (none shown). Thefront rotating body can be connected to the crankshaft 12B without theone-way clutch.

The operation unit 14 is provided on the bicycle 10. The operation unit14 is configured to communicate with an electronic control unit 32 ofthe bicycle controller 30 through a wired connection or a wirelessconnection. The operation unit 14 includes, for example, an operationmember, a sensor that detects movement of the operation member, and anelectronic circuit that performs communication with the electroniccontrol unit 32 in accordance with the output signal of the sensor. Theoperation unit 14 includes one or more operation members that changeriding modes of the motor 22. The operation members include a pushswitch, a lever type switch and a touch panel. If a rider operates theoperation unit 14, then the operation unit 14 transmits a switch signalthat switches riding modes of the bicycle 10 to the electronic controlunit 32. The riding modes include a first mode and a second mode. Thefirst mode is suitable for rough roads that are bumpy. The second modeis suitable for even roads.

The battery 16 includes one or more battery cells. The battery cellsinclude rechargeable batteries. The battery 16 is electrically connectedto a motor 22 of the assist device 18 to supply the motor 22 with power.The battery 16 supplies power to the bicycle controller 30 and otherelectronic components that are mounted on the bicycle 10 andelectrically connected to the battery 16 by wires.

The assist device 18 includes a drive circuit 20 and the motor 22. Thedrive circuit 20 controls the power supplied from the battery 16 to themotor 22. The motor 22 assists propulsion of the bicycle 10. The motor22 includes an electric motor. The motor 22 is configured to transmitrotation to a manual driving force transmission path, which extends fromthe pedals 12D to a rear wheel (not shown) or a front wheel (not shown).The motor 22 is arranged on a frame (not shown), the rear wheel, or thefront wheel of the bicycle 10. In one example, the motor 22 is connectedto a power transmission path that extends from the crankshaft 12B to afront rotating body. It is preferred that the power transmission pathfrom the motor 22 to the crankshaft 12B include a one-way clutch (notshown) that is configured so that the crank rotation force produced bythe rotation of the crankshaft 12B to move the bicycle forward does notaffect the rotation produced by the motor 22. The assist device 18 caninclude a reduction gear that reduces the speed of the rotation producedby the motor 22 before outputting the rotation.

The bicycle controller 30 includes the electronic control unit 32. Inone example, the bicycle controller 30 further includes a memory 34, aninclination detector 36, a torque sensor 38, and a rotational anglesensor 40.

The electronic control unit 32 includes one or more processors thatexecutes predetermined control programs. The processor(s) includes, forexample, a central processing unit (CPU) or a micro-processing unit(MPU). The memory 34 stores information used for various controlprograms and various control processes. The memory 34 includes, forexample, a non-volatile memory and a volatile memory. The memory 34 isone or more storage devices (i.e., one or more computer memory devices).The memory 34 can be, for example, any a non-transitory computerreadable medium such as a ROM (Read Only Memory) device, a RAM (RandomAccess Memory) device, a hard disk, a flash drive, etc. The memory 34 isconfigured to store settings, programs, data, calculations and/orresults of the processor(s) of the electronic control unit 32.

The inclination detector 36 detects an inclination angle D of thebicycle 10. The inclination detector 36 is configured to communicatewith the electronic control unit 32 through a wired connection or awireless connection. The inclination detector 36 includes a three-axisgyro sensor 36A and a three-axis acceleration sensor 36B. The output ofthe inclination detector 36 includes information related to the attitudeangle on each of the three axes and the acceleration on each of thethree axes. The three attitude angles include a pitch angle DA, a rollangle DB and a yaw angle DC. Preferably, the three axes of the gyrosensor 36A coincide with the three axes of the acceleration sensor 36B.The inclination detector 36 corrects the output of the gyro sensor 36Ain accordance with the output of the acceleration sensor 36B and sends asignal to the electronic control unit 32 corresponding to theinclination angle D of the bicycle 10. The inclination angle D of thebicycle 10 is the absolute value of the pitch angle DA. In a case inwhich the bicycle 10 is traveling on an uphill, the pitch angle DA ispositive. In a case in which the bicycle 10 is traveling on an uphill,an increase in the inclination angle D corresponds to an increase in thepitch angle DA. In a case in which the bicycle 10 is traveling on adownhill, the pitch angle DA is negative. In a case in which the bicycle10 is on a downhill, an increase in the inclination angle D correspondsto a decrease in the pitch angle DA. The assist device 18 can include aone-axis acceleration sensor or a two-axis acceleration sensor insteadof the gyro sensor 36A and the acceleration sensor 36B.

The torque sensor 38 outputs a signal that is in accordance with amanual driving force T. The torque sensor 38 detects the manual drivingforce T applied to the crankshaft 12B. The torque sensor 38 can bearranged between the crankshaft 12B and the front rotating body (notshown). Alternatively, the torque sensor 38 can be arranged on thecrankshaft 12B or the front sprocket. As another option, the torquesensor 38 can be arranged on the crank arms 12C or the pedals 12D. Thetorque sensor 38 can be realized by, for example, a strain sensor, amagnetostrictive sensor, an optical sensor, a pressure sensor, or thelike. Any sensor can be used as the torque sensor 38 as long as thesensor outputs a signal corresponding to the manual driving force Tapplied to the crank arms 12C or the pedals 12D.

The rotational angle sensor 40 detects a crank rotation speed N and arotational angle of the crank 12A. The rotational angle sensor 40 isattached to the frame (not shown) of the bicycle 10 or a housing (notshown) of the assist device 18. The rotational angle sensor 40 includesa first element 40A and a second element 40B. The first element 40Adetects the magnetic field of a first magnet M1. The second element 40Boutputs a signal corresponding to the positional relationship with asecond magnet M2. The first magnet M1 is arranged on the crankshaft 12Bor the crank arms 12C and coaxial with the crankshaft 12B. The firstmagnet M1 is an annular magnet, in which multiple magnetic poles arealternately arranged in the circumferential direction. The first element40A detects the rotational angle of the crank 12A relative to the frame.The first element 40A outputs a signal as the crank 12A completes asingle rotation. A single cycle of the signal corresponds to the angleobtained by dividing 360 degrees by the number of magnetic poles havingthe same polarity. The minimum value of the rotational angle of thecrank 12A that is detectable by the rotational angle sensor 40 is 180degrees or smaller, preferably, 15 degrees, and further preferably, 6degrees. The second magnet M2 is arranged on the crankshaft 12B or thecrank arms 12C. The second element 40B detects a reference angle of thecrank 12A relative to the frame (e.g., top dead center or bottom deadcenter of crank 12A). The second element 40B outputs a signal of which asingle cycle is one rotation of the crankshaft 12B.

Instead of the first element 40A and the second element 40B, therotational angle sensor 40 can include a magnetic sensor that outputs asignal in accordance with the intensity of the magnetic field. In thiscase, instead of the first magnet M1 and the second magnet M2, anannular magnet of which the magnetic field intensity varies in thecircumferential direction is arranged on the crankshaft 12B coaxiallywith the crankshaft 12B. The use of the magnetic sensor that outputs asignal corresponding to the magnetic field intensity allows the crankrotation speed N and the rotational angle of the crank 12A to bedetected with a single sensor. This simplifies the structure andfacilitates the assembling.

The electronic control unit 32 is configured (programmed) control themotor 22 in accordance with the manual driving force T. The electroniccontrol unit 32 uses a low-pass filter 52 to change the response speedof the motor 22 with respect to changes in the manual driving force T.The electronic control unit 32 is configured to change the responsespeed of the motor 22 if the manual driving force T decreases. Theresponse speed of the motor 22 in a case in which the manual drivingforce T decreases is referred to as the response speed R.

The electronic control unit 32 is configured to change the responsespeed R in accordance with the inclination angle D of the bicycle 10.The electronic control unit 32 is configured to change the responsespeed R in a stepped manner in accordance with the inclination angle Dof the bicycle 10. Further, the electronic control unit 32 is configuredto change the response speed R in accordance with the crank rotationspeed N. The electronic control unit 32 is configured to switch betweenthe first mode and the second mode in accordance with the operation ofthe operation unit 14. The first mode and the second mode differ fromeach other in the response speed R with respect to the inclination angleD and the crank rotation speed N.

As the inclination angle D of the bicycle 10 increases on an uphill, theelectronic control unit 32 is configured to decrease the response speedR of the motor 22. As the inclination angle D of the bicycle 10 on anuphill becomes greater than or equal to a first angle D1, the electroniccontrol unit 32 is configured to fix the response speed R. Morespecifically, in the first mode, the electronic control unit 32 isconfigured to decrease the response speed of the motor 22 as theinclination angle D of the bicycle 10 increases on an uphill. Further,in the first mode, the electronic control unit 32 is configured to fixthe response speed R as the inclination angle D of the bicycle 10 on anuphill becomes greater than or equal to the first angle D1. In thesecond mode, the electronic control unit 32 is also configured todecrease the response speed of the motor 22 as the inclination angle Dof the bicycle 10 increases on an uphill.

As the inclination angle D of the bicycle 10 increases on a downhill,the electronic control unit 32 is configured to increase the responsespeed R. As the inclination angle D of the bicycle 10 on a downhillbecomes greater than or equal to a second angle D2, the electroniccontrol unit 32 is configured to fix the response speed R. Morespecifically, in the second mode, the electronic control unit 32 isconfigured to increase the response speed R as the inclination angle Dof the bicycle 10 increases on a downhill. Further, in the second mode,the electronic control unit 32 is configured to fix the response speed Ras the inclination angle D of the bicycle 10 on a downhill becomesgreater than or equal to the second angle D2. In the first mode, theelectronic control unit 32 can also increase the response speed R as theinclination angle D of the bicycle 10 increases on a downhill and fixthe response speed R as the inclination angle D of the bicycle 10 on adownhill becomes greater than or equal to the second angle D2.

The electronic control unit 32 is configured to control the motor 22 inthe first mode that decreases the response speed R as the crank rotationspeed N increases. Further, in the first mode, the electronic controlunit 32 fixes the response speed R as the crank rotation speed N becomeshigher than or equal to a first speed N1. The electronic control unit 32is also configured to control the motor 22 in the second mode thatincreases the response speed R as the crank rotation speed N increases.Further, in the second mode, the electronic control unit 32 isconfigured to fix the response speed R as the crank rotation speed Nbecomes higher than or equal to a second speed N2.

The electronic control unit 32 includes a mode switching unit 42, amanual driving force computation unit 44, an increase-decreasedetermination unit 46, a correction unit 48 and an output computationunit 50. The processor of the electronic control unit 32 executesprograms to function as the mode switching unit 42, the manual drivingforce computation unit 44, the increase-decrease determination unit 46,the correction unit 48 and the output computation unit 50.

The mode switching unit 42 switches the riding mode of the bicycle 10based on a switch signal from the operation unit 14. In a case in whichthe mode switching unit 42 receives a switch signal from the operationunit 14 for switching the riding mode to the first mode, the modeswitching unit 42 transmits a signal to the correction unit 48 forsetting a first map that corresponds to the first mode and is stored inthe memory 34. In a case in which the mode switching unit 42 receives aswitch signal from the operation unit 14 for switching the riding modeto the second mode, the mode switching unit 42 transmits a signal to thecorrection unit 48 for setting a second map that corresponds to thesecond mode and is stored in the memory 34.

The manual driving force computation unit 44 is configured to computethe manual driving force T based on the output from the torque sensor38. The increase-decrease determination unit 46 determines whether themanual driving force T is increasing or decreasing. For example, theincrease-decrease determination unit 46 determines whether the manualdriving force T in the present computation cycle has increased ordecreased from the manual driving force T of the previous computationcycle.

The correction unit 48 includes the low-pass filter 52 and a responsespeed setting unit 54. The correction unit 48 is configured to correctthe manual driving force T. The low-pass filter 52 is a linear low-passfilter. The low-pass filter 52 uses a time constant K to correct themanual driving force T to a corrected driving force TX. An increase inthe time constant K decreases the response speed R and retards changingof the corrected driving force TX with respect to the manual drivingforce T.

The response speed setting unit 54 sets the time constant K used by thelow-pass filter 52. The response speed setting unit 54 sets the timeconstant K based on the first or second map, which is set by the modeswitching unit 42, the inclination angle D, and the crank rotation speedN.

The output computation unit 50 is configured to compute the output ofthe motor 22 (hereinafter referred to as “the motor output TM”) based onthe manual driving force T. The output computation unit 50 computes themotor output TM as, for example, at least one of the motor torque andthe motor rotation speed. The output computation unit 50 selects one ofthe manual driving force T and the corrected driving force TX based onthe determination result of the increase-decrease determination unit 46and the comparison result of the manual driving force T and thecorrected driving force TX. Then, the output computation unit 50computes the motor output TM based on the selected one of the manualdriving force T and the corrected driving force TX. More specifically,in a case in which the manual driving force T decreases, the outputcomputation unit 50 computes the motor output TM by multiplying thecorrected driving force TX by a predetermined value. In a case in whichthe manual driving force T increases and the manual driving force T isless than the corrected driving force TX, the output computation unit 50computes the motor output TM by multiplying the corrected driving forceTX by a predetermined value. In a case in which the manual driving forceT increases and the manual driving force T is greater than or equal thecorrected driving force TX, the output computation unit 50 computes themotor output TM by multiplying the manual driving force T by apredetermined value. The predetermined value is changed in accordancewith the riding mode. The ratio of the motor output TM to the manualdriving force T differs between riding mode. The rider switches theriding mode by operating the operation unit 14. The electronic controlunit 32 sends a control signal to the drive circuit 20 based on thecomputed motor output TM.

The motor control executed by the electronic control unit 32 will now bedescribed with reference to FIG. 2. While the electronic control unit 32is being supplied with power, the motor control is executed inpredetermined cycles. In step S11, the electronic control unit 32computes the manual driving force T. In step S12, the electronic controlunit 32 determines whether or not the present riding mode is the firstmode. If the electronic control unit 32 determines that the riding modeis the first mode, then the electronic control unit 32 proceeds to stepS13. In step S13, the electronic control unit 32 computes the correcteddriving force TX based on the first map, the inclination angle D, thecrank rotation speed N and the manual driving force T. Then, theelectronic control unit 32 proceeds to step S14.

In step S14, the electronic control unit 32 determines whether or notthe manual driving force T is decreasing. For example, if the manualdriving force T in the present computation cycle is less than the manualdriving force T in the preceding computation cycle, then the electroniccontrol unit 32 determines that the manual driving force T isdecreasing.

If the electronic control unit 32 determines in step S14 that the manualdriving force T is decreasing, then the electronic control unit 32proceeds to step S15 and computes the motor output TM based on thecorrected driving force TX, which was computed in step S13. Then, theelectronic control unit 32 proceeds to step S16. In step S16, theelectronic control unit 32 controls the motor 22 based on the motoroutput TM. Then, after a predetermined cycle, the electronic controlunit 32 starts the process again from step S11.

In a case in which the first mode is selected and the crank rotationspeed N does not change, the response speed R is decreased as theinclination angle D increases on an uphill. In a case in which the firstmode is selected and the inclination angle D on an uphill is greaterthan or equal to the first angle D1, the response speed R is set to afirst value R1. In a case in which the first mode is selected and theinclination angle D does not change, the response speed R is decreasedif the crank rotation speed N is increased. In a case in which the firstmode is selected and the crank rotation speed N is higher than or equalto the first speed N1, the response speed R is fixed.

Referring to FIG. 3, in the first map, the time constant K for a givencrank rotation speed N increases as the pitch angle DA increases. Thus,in the first map, as the inclination angle D increases on an uphill, thetime constant K for a given crank rotation speed N increases, and theresponse speed R decreases.

In FIG. 3, a first line L11 indicates the relationship of the crankrotation speed N and the time constant K in a case in which the pitchangle DA is a first pitch angle DA1. The first line L11 is the solidline. A second line L12 indicates the relationship of the crank rotationspeed N and the time constant K in a case in which the pitch angle DA isa second pitch angle DA2. The second line L12 is the dotted line. Athird line L13 indicates the relationship of the crank rotation speed Nand the time constant K in a case in which the pitch angle DA is a thirdpitch angle DA3. The third line L13 is the single-dashed line. The firstpitch angle DA1, the second pitch angle DA2, and the third pitch angleDA3 have a relationship of DA1>DA2>DA3. The first pitch angle DA1, whichis a positive value, is the pitch angle DA of the bicycle 10 thatcorresponds to a road gradient of 10%. In a case in which the pitchangle DA is the first pitch angle DA1, the inclination angle D of thebicycle 10 on an uphill is the first angle D1. In one example, the firstpitch angle DA1 is +5.7 degrees, the second pitch angle DA2 is +2.8degrees, and the third pitch angle DA3 is 0 degrees.

In the first map, the time constant K is constant if the pitch angle DAis greater than or equal to the first pitch angle DA1. As shown by thefirst line L11, if the pitch angle DA is the first pitch angle DA1, thena first predetermined value K1 is selected as the time constant Kregardless of the crank rotation speed N.

In the first map, the time constant K increases as the crank rotationspeed N increases if the pitch angle DA is less than the first pitchangle DA1. Further, in the first map, the time constant K is constant ifthe crank rotation speed N becomes higher than or equal to the firstspeed N1 if the pitch angle DA is less than the first pitch angle DA1.In one example, in a case in which the crank rotation speed N becomeshigher than or equal to the first speed N1 if the pitch angle DA is lessthan the first pitch angle DA1, the time constant K is equal to the timeconstant K1, which is for a case in which the pitch angle DA is greaterthan or equal to the first pitch angle DA1.

As shown by the second line L12, if the pitch angle DA is the secondpitch angle DA2, then the time constant K increases in a linear manneras the crank rotation speed N increases, and the time constant K is setto the first predetermined value K1 as the crank rotation speed Nbecomes higher than or equal to the first speed N1. As shown by thethird line L13, if the pitch angle DA is the third pitch angle DA3, thenthe time constant K increases in a linear manner as the crank rotationspeed N increases, and the time constant is set to the firstpredetermined value K1 as the crank rotation speed N becomes higher thanor equal to the first speed N1. If the pitch angle DA is the third pitchangle DA3 and the crank rotation speed N is lower than the first speedN1, under a condition in which the crank rotation speed N is the same,then the time constant K is less than that for a case in which the pitchangle DA is the second pitch angle DA2.

In the first map, the relationship of the crank rotation speed N and thetime constant K in a case in which the crank rotation speed N is lowerthan or equal to the first speed N1 is set in advance with a firstcomputation equation. The first computation equation includes acoefficient that is determined in accordance with the inclination angleD. The first computation equation is, for example, as shown below byequation (1).

K=(4×A1×N)+(L1×A2)  (1)

In equation (1), “L1” represents a constant, “N” represents the crankrotation speed N, “A1” represents a coefficient determined in accordancewith the inclination angle D, and “A2” represents a coefficientdetermined in accordance with the inclination angle D. Further, “A1” isset to decrease as the inclination angle D increases, and “A2” is set toincrease as the inclination angle D increases. Table 1 shows one exampleof the relationship of “A1” and “A2” with respect to the inclinationangle D.

TABLE 1 Pitch Inclination Angle Road Angle Gradient A1 A2 1st Pitch+5.7° Uphill 5.7° +10% 0 2 Angle DA1 2nd Pitch +2.8° Uphill 2.8° +5% 0.51.0 angle DA2 3rd Pitch 0°  0°   0% 1.0 0 Angle DA3

As shown in FIG. 2, if the electronic control unit 32 determines in stepS12 that the present riding mode is not the first mode, that is, thepresent mode is the second mode, then the electronic control unit 32proceeds to step S17. In step S17, the electronic control unit 32computes the corrected driving force TX based on the second map, theinclination angle D, the crank rotation speed N and the manual drivingforce T. Then, the electronic control unit 32 proceeds to step S14.

In step S14, the electronic control unit 32 determines whether or notthe manual driving force T is decreasing. If the electronic control unit32 determines in step S14 that the manual driving force T is decreasing,in step S15, then the electronic control unit 32 computes the motoroutput TM based on the corrected driving force TX, which has beencomputed in step S17, and proceeds to step S16. In step S16, theelectronic control unit 32 controls the motor 22 based on the motoroutput TM. Then, after a predetermined cycle, the electronic controlunit 32 starts the process again from step S11.

In a case in which the second mode is selected and the crank rotationspeed N does not change, the response speed R increases as theinclination angle D increases on a downhill. In a case in which thesecond mode is selected and the inclination angle D is less than orequal to the second angle D2 on a downhill, the response speed R is asecond value R2. The response speed R is the highest if it is the secondvalue R2. In one example, the second value R2 is equal to the responsespeed R if the manual driving force T is increasing. In a case in whichthe second mode is selected and the inclination angle D does not change,the response speed R is increased as the crank rotation speed Nincreases. In a case in which the second mode is selected and the crankrotation speed N becomes higher than or equal to the second speed N2,the response speed R is fixed.

As shown in FIG. 4, in the second map, the time constant K for a givencrank rotation speed N increases as the pitch angle DA increases. Thus,in the second map, as the inclination angle D increases on a downhill,the time constant K for a given crank rotation speed N decreases. Thisdecreases the response speed R.

In FIG. 4, a first line L21 indicates the relationship of the crankrotation speed N and the time constant K in a case in which the pitchangle DA is a fourth pitch angle DA4. The first line L21 is the solidline. A second line L22 indicates the relationship of the crank rotationspeed N and the time constant K in a case in which the pitch angle DA isa fifth pitch angle DA5. The second line L22 is the single-dashed line.A third line L23 indicates the relationship of the crank rotation speedN and the time constant K in a case in which the pitch angle DA is asixth pitch angle DA6. The third line L23 is the dashed line. A fourthline L24 indicates the relationship of the crank rotation speed N andthe time constant K in a case in which the pitch angle DA is a seventhpitch angle DA7. The fourth line L24 is the dotted line. A fifth lineL25 indicates the relationship of the crank rotation speed N and thetime constant K in a case in which the pitch angle DA is an eighth pitchangle DA8. The fifth line L25 is the double-dashed line. The fourthpitch angle DA4, the fifth pitch angle DA5, the sixth pitch angle DA6,the seventh pitch angle DA7, and the eighth pitch angle DA8 have arelationship of DA4<DA5<DA6<DA7<DA8. The fourth pitch angle DA4, whichis a negative value, is the pitch angle DA of the bicycle 10corresponding to a road gradient of, for example, minus 10%. If thepitch angle DA is the fourth pitch angle DA4, then the inclination angleD of the bicycle 10 on a downhill is the second angle D2. In oneexample, the fourth pitch angle DA4 is −5.7 degrees, the fifth pitchangle DA5 is −2.8 degrees, the sixth pitch angle DA6 is zero degrees,the seventh pitch angle DA7 is +2.8 degrees, and the eighth pitch angleDA8 is +5.7 degrees.

In the second map, the time constant K is constant if the pitch angle DAis less than or equal to the fourth pitch angle DA4. As shown by thefirst line L21, in a case in which the pitch angle DA is the fourthpitch angle DA4, a second predetermined value K2 is selected as the timeconstant K regardless of the crank rotation speed N. The secondpredetermined value K2 is, for example, 0.

In the second map, the time constant K decreases as the crank rotationspeed N increases if the pitch angle DA is greater than the fourth pitchangle DA4. Further, in the second map, the time constant K is constantif the crank rotation speed N becomes higher than or equal to the secondspeed N2 if the pitch angle DA is greater than the fourth pitch angleDA4. In one example, in a case in which the crank rotation speed Nbecomes higher than or equal to the second speed N2 if the pitch angleDA is greater than the fourth pitch angle DA4, the time constant K isequal to the time constant K2 for a case in which the pitch angle DA isless than or equal to the fourth pitch angle DA4.

As shown by the second line L22, if the pitch angle DA is the fifthpitch angle DA5, then the time constant K decreases in an exponentialmanner as the crank rotation speed N increases, and the time constant Kis set to the second predetermined value K2 if the crank rotation speedN becomes higher than or equal to the second speed N2.

As shown by the third line L23, if the pitch angle DA is the sixth pitchangle DA6, then the time constant K decreases in an exponential manneras the crank rotation speed N increases, and the time constant K is setto the second predetermined value K2 if the crank rotation speed Nbecomes higher than or equal to the second speed N2. If the pitch angleDA is the sixth pitch angle DA6 and the crank rotation speed N is lowerthan the second speed N2, under a condition in which the crank rotationspeed N is the same, then the time constant K is greater than that for acase in which the pitch angle DA is the fifth pitch angle DA5.

As shown by the fourth line L24, if the pitch angle DA is the seventhpitch angle DA7, then the time constant K decreases in an exponentialmanner as the crank rotation speed N increases, and the time constant Kis set to the second predetermined value K2 if the crank rotation speedN becomes higher than or equal to the second speed N2. If the pitchangle DA is the seventh pitch angle DA7 and the crank rotation speed Nis lower than the second speed N2, under a condition in which the crankrotation speed N is the same, then the time constant K is greater thanthat for a case in which the pitch angle DA is the sixth pitch angleDA6.

As shown by the fifth line L25, if the pitch angle DA is the eighthpitch angle DA8, then the time constant K decreases in an exponentialmanner as the crank rotation speed N increases, and the time constant Kis set to the second predetermined value K2 if the crank rotation speedN becomes higher than or equal to the second speed N2. If the pitchangle DA is the eighth pitch angle DA8 and the crank rotation speed N islower than the second speed N2, under a condition in which the crankrotation speed N is the same, then the time constant K is greater thanthat for a case in which the pitch angle DA is the seventh pitch angleDA7.

In the second map, the relationship of the crank rotation speed N andthe time constant K if the crank rotation speed N is lower than or equalto the second speed N2 is set in advance with a second computationequation. The second computation equation includes a coefficient that isdetermined in accordance with the pitch angle DA. The second computationequation is, for example, as shown below by equation (2).

K=(L2×B)÷100÷N×1000  (2)

In equation (2), “L2” represents a constant, “N” represents the crankrotation speed N, and “B” represents a coefficient determined inaccordance with the pitch angle DA. Further, “B” is set to increase asthe pitch angle DA increases. Table 2 shows one example of therelationship of “B” and the pitch angle DA.

TABLE 2 Pitch Inclination Angle Road Angle Gradient B 4th Pitch −5.7°Downhill 5.7° −10%  0 Angle DA4 5th Pitch −2.8° Downhill 2.8° −5% 0.5Angle DA5 6th Pitch 0°  0°    0% 1.0 Angle DA6 7th Pitch +2.8° Uphill2.8° +5% 1.5 Angle DA7 8th Pitch +5.7° Uphill 5.7° +10%  2.0 Angle DA8

As shown in FIG. 2, if the electronic control unit 32 determines in stepS14 that the manual driving force T is not decreasing, then theelectronic control unit 32 proceeds to step S18 and determines whetheror not the manual driving force T is greater than the corrected drivingforce TX. If the electronic control unit 32 determines in step S18 thatthe manual driving force T is greater than the corrected driving forceTX, then the electronic control unit 32 proceeds to step S19 andcomputes the motor output TM based on the manual driving force T. Then,the electronic control unit 32 proceeds to step S16. In step S16, theelectronic control unit 32 controls the motor 22 based on the motoroutput TM. Then, after a predetermined cycle, the electronic controlunit 32 starts the process again from step S11.

If the electronic control unit 32 determines in step S18 that the manualdriving force T is less than or equal to the corrected driving force TX,then the electronic control unit 32 proceeds to step S15 and computesthe motor output TM based on the corrected driving force TX. Then, theelectronic control unit 32 proceeds to step S16. In step S16, theelectronic control unit 32 controls the motor 22 based on the motoroutput TM. Then, after a predetermined cycle, the electronic controlunit 32 starts the process again from step S11. In this manner, duringthe period in which the manual driving force T is increasing, theelectronic control unit 32 controls the motor 22 based on the greaterone of the manual driving force T and the corrected driving force TX.

With reference to FIG. 5, one example of the motor control that isexecuted in a case in which the first mode is selected will now bedescribed. Timing chart A of FIG. 5 shows the relationship of time andthe manual driving force T. Timing chart B of FIG. 5 shows therelationship of time and the pitch angle DA. Timing chart C of FIG. 5shows the relationship of time and the motor output TM. Further, thetiming charts A to C of FIG. 5 show a state in which the crank rotationspeed N is constant as the bicycle 10 travels. In the timing chart C ofFIG. 5, the solid line represents the motor output TM in a case in whichthe inclination angle D changes as the bicycle 10 travels, and thedouble-dashed line represents the motor output TM in a case in which theinclination angle D does not change as the bicycle 10 travels.

In the timing charts A to C of FIG. 5, in the period from time t10 totime t11, the pitch angle DA is greater than or equal to the first pitchangle DA1. During this period, in a case in which the manual drivingforce T is greater than the corrected driving force TX, if the manualdriving force T is increased, that is, if the crank arms 12C (refer toFIG. 1) are rotated from the top dead center or the bottom dead centertoward an intermediate angle between the top dead center and the bottomdead center, then the motor output TM is changed at an increase ratethat is substantially equal to the increase rate of the manual drivingforce T. If the manual driving force T is decreased, that is, if thecrank arms 12C (refer to FIG. 1) are rotated from an intermediate anglebetween the top dead center and the bottom dead center toward the topdead center or the bottom dead center, then the motor output TM isdecreased at a decrease rate that is more gradual than the decrease rateof the manual driving force T.

At time t11, the pitch angle DA becomes less than or equal to the firstpitch angle DA1 but is greater than the second pitch angle DA2. Here,the electronic control unit 32 decreases the time constant K inaccordance with the pitch angle DA. Thus, the decrease rate of thecorrected driving force TX becomes greater than the decrease rate of theperiod from time t10 to t11, and the decrease rate of the correcteddriving force TX approaches the decrease rate of the manual drivingforce T. Further, the decrease rate of the motor output TM approachesthe decrease rate of the manual driving force T. That is, the responsespeed R of the motor 22 is increased with respect to a change in themanual driving force T. In a case in which the pitch angle DA remainsless than or equal to the first pitch angle DA1 but greater than thesecond pitch angle DA2, if the manual driving force T decreases, thenthe electronic control unit 32 controls the motor 22 with a fixedresponse speed R.

At time t12, the pitch angle DA becomes less than or equal to the secondpitch angle DA2 but is greater than the third pitch angle DA3. Thus, thedecrease rate of the corrected driving force TX becomes greater than thedecrease rate of the period from time t11 to time t12. Further, thedecrease rate of the motor output TM further approaches the decreaserate of the manual driving force T. That is, the response speed R of themotor 22 is increased with respect to the manual driving force T. In acase in which the pitch angle DA remains greater than or equal to thethird pitch angle DA3, if the manual driving force T is decreased, thenthe electronic control unit 32 controls the motor 22 with a fixedresponse speed R.

With reference to FIG. 6, one example of the motor control in a case inwhich the second mode is selected will now be described. Timing chart Aof FIG. 6 shows the relationship of time and the manual driving force T.Timing chart B of FIG. 6 shows the relationship of time and the pitchangle DA. Timing chart C of FIG. 6 shows the relationship of time andthe motor output TM. Further, the timing charts A to C of FIG. 6 show astate in which the crank rotation speed N is constant as the bicycle 10travels. In the timing chart C of FIG. 6, the solid line represents themotor output TM in a case in which the inclination angle D changes asthe bicycle 10 travels, and the double-dashed line represents the motoroutput TM in a case in which the inclination angle D does not change asthe bicycle 10 travels.

In the timing charts A to C of FIG. 6, in the period from time t20 tot21, the pitch angle DA is less than or equal to the sixth pitch angleDA6 but greater than the fifth pitch angle DA5. During this period, in acase in which the manual driving force T is greater than the correcteddriving force TX, if the manual driving force T is increased, then themotor output TM is changed at an increase rate that is substantiallyequal to the increase rate of the manual driving force T. If the manualdriving force T is decreased, then the motor output TM is decreased at adecrease rate that is more gradual than the decrease rate of the manualdriving force T.

At time t21, the pitch angle DA becomes less than or equal to the fifthpitch angle DA5 but is greater than the fourth pitch angle DA4. Here,the electronic control unit 32 decreases the time constant K inaccordance with the pitch angle DA. Thus, the decrease rate of thecorrected driving force TX is increased, and the decrease rate of thecorrected driving force TX approaches the decrease rate of the manualdriving force T. Further, the decrease rate of the motor output TMapproaches the decrease rate of the manual driving force T. That is, theresponse speed R of the motor 22 is increased with respect to a changein the manual driving force T. In a case in which the pitch angle DAremains less than or equal to the fifth pitch angle DA5 and greater thanthe fourth pitch angle DA4, if the manual driving force T decreases,then the electronic control unit 32 controls the motor 22 with a fixedresponse speed R.

At time t22, the pitch angle DA becomes less than or equal to the fourthpitch angle DA4. Here, the electronic control unit 32 sets the timeconstant K to “0.” Thus, the decrease rate of the corrected drivingforce TX is increased, and the decrease rate of the corrected drivingforce TX becomes substantially equal to the decrease rate of the manualdriving force T. Further, the decrease rate of the motor output TMbecomes substantially equal to the decrease rate of the manual drivingforce T. That is, the response speed R of the motor 22 is increased withrespect to a change in the manual driving force T. In a case in whichthe pitch angle DA remains less than or equal to the fourth pitch angleDA4, the electronic control unit 32 controls the motor 22 with a fixedresponse speed R.

The advantages of the bicycle controller 30 will now be described.

The bicycle controller 30 keeps the motor output TM high in a case inwhich the inclination angle D is large on an uphill. This reduces theload on the rider in a case in which the rider rides the bicycle 10 onan uphill. The bicycle controller 30 changes the motor output TM with ahigh responsivity in accordance with changes in the manual driving forceT on a downhill or an even road. This allows the rider to easily controlthe bicycle 10 while riding downhill or on an even road.

The force acting on the rear of the bicycle 10 in a case in which thebicycle 10 travels off-road on a bumpy uphill is greater than that in acase in which the bicycle 10 is traveling on an even uphill. In such acase, as long as the first mode is selected, the bicycle controller 30will function so that the rider hardly notices any lack in the motoroutput TM.

Second Embodiment

With reference to FIGS. 1 and 7 to 9, a second embodiment of the bicyclecontroller 30 will now be described. The second embodiment of thebicycle controller 30 is similar to the first embodiment of the bicyclecontroller 30 except in that a response speed Q of the motor 22 changesin accordance with the inclination angle D even in a case in which themanual driving force T increases. Same reference numerals are given tothose components that are the same as the corresponding components ofthe first embodiment. Such components will not be described in detail.

In a case in which the manual driving force T increases, the electroniccontrol unit 32 changes the response speed of the motor 22. The responsespeed of the motor 22 in a case in which the manual driving force Tincreases is referred to as the response speed Q. The electronic controlunit 32 can change the response speed Q in a stepped manner inaccordance with the inclination angle D of the bicycle 10.Alternatively, the electronic control unit 32 can change the responsespeed Q in a continuous manner in accordance with the inclination angleD of the bicycle 10.

In a case in which the inclination angle D of the bicycle 10 increaseson an uphill, the electronic control unit 32 increases the responsespeed Q. In a case in which the inclination angle D of the bicycle 10increases on an uphill, the electronic control unit 32 increases theresponse speed Q of the motor 22 as the manual driving force Tincreases. In a case in which the inclination angle D of the bicycle 10becomes greater than or equal to a first angle D1 on an uphill, theelectronic control unit 32 fixes the response speed Q if the manualdriving force T increases.

In a case in which the inclination angle D of the bicycle 10 increaseson a downhill, the electronic control unit 32 decreases the responsespeed Q. In a case in which the inclination angle D of the bicycle 10increases on a downhill, the electronic control unit 32 decreases theresponse speed Q as the manual driving force T increases. In a case inwhich the inclination angle D of the bicycle 10 becomes greater than orequal to a second angle D2 on a downhill, the electronic control unit 32fixes the response speed Q if the manual driving force T increases.

The memory 34 stores a third map and a fourth map that set therelationship of the increasing speed of the manual driving force T, theinclination angle D, and a corrected value CX. In a case in which themanual driving force T increases, the electronic control unit 32 addsthe corrected value CX to the manual driving force T or multiplies themanual driving force T by the corrected value CX to calculate acorrected driving force TX.

The third map sets the corrected value CX for cases in which the manualdriving force T increases in the first mode. In one example, in thethird map, the corrected value CX is set to increase as the increasingspeed of the manual driving force T increases. Further, the correctedvalue CX is set to increase as the pitch angle DA increases. The fourthmap sets the corrected value CX for cases in which the manual drivingforce T increases in the second mode. In one example, in the fourth map,the corrected value CX is set to increase as the increasing speed of themanual driving force T increases. Further, the corrected value CX is setto decrease as the pitch angle DA increases. In the third map,regardless of the increasing speed of the manual driving force T, thecorrected value CX can be set to increase as the pitch angle DAincreases. In the fourth map, regardless of the increasing speed of themanual driving force T, the corrected value CX can be set to decrease asthe pitch angle DA decreases.

In a case in which the electronic control unit 32 adds the correctedvalue CX to the manual driving force T to calculate the correcteddriving force TX, in the third and fourth maps, if the increasing speedof the manual driving force T is less than a predetermined speed, thenthe corrected value CX can be a negative value. In a case in which theelectronic control unit 32 multiples the manual driving force T by thecorrected value CX to calculate the corrected driving force TX, in thethird and fourth maps, if the increasing speed of the manual drivingforce T is less than a predetermined speed, then the corrected value CXcan be less than 1.

With reference to FIG. 7, the motor control executed by the electroniccontrol unit 32 will now be described. In a state in which theelectronic control unit 32 is being supplied with power, the motorcontrol is executed in predetermined cycles. In step S31, the electroniccontrol unit 32 calculates the manual driving force T. In step S32, theelectronic control unit 32 determines whether or not the present ridingmode is the first mode. The electronic control unit 32 proceeds to stepS33 if the electronic control unit 32 determines that the riding mode isthe first mode.

In step S33, the electronic control unit 32 determines whether or notthe manual driving force T is decreasing. If the electronic control unit32 determines that the manual driving force T is decreasing, then theelectronic control unit 32 proceeds to step S34. In step S34, theelectronic control unit 32 calculates the corrected driving force TXbased on the first map, the inclination angle D, the crank rotationspeed N, and the manual driving force T and then proceeds to step S35.In step S35, the electronic control unit 32 calculates the motor outputTM based on the calculated corrected driving force TX and proceeds tostep S36. In step S36, the electronic control unit 32 controls the motor22 based on the motor output TM and then executes the processing fromstep S31 again after a predetermined cycle.

If the electronic control unit 32 determines in step S33 that the manualdriving force T is increasing or not changing, then the electroniccontrol unit 32 proceeds to step S37. In step S37, the electroniccontrol unit 32 calculates the corrected driving force TX based on thethird map, the inclination angle D, and the manual driving force T andthen proceeds to step S35. More specifically, the electronic controlunit 32 calculates the corrected driving force TX by adding thecorrected value CX, which is set in the third map, to the increasingspeed of the manual driving force T or multiplying the increasing speedof the manual driving force T by the corrected value CX, which is set inthe third map. In step S35, the electronic control unit 32 calculatesthe motor output TM based on the calculated corrected driving force TXand then proceeds to step S36. In step S36, the electronic control unit32 controls the motor 22 based on the motor output TM and then executesthe processing from step S31 again after a predetermined cycle.

If the electronic control unit 32 determines in step S32 that thepresent riding mode is not the first mode, that is, the present ridingmode is the second mode, then the electronic control unit 32 proceeds tostep S38. In step S38, the electronic control unit 32 determines whetheror not the manual driving force T is decreasing. If the electroniccontrol unit 32 determines that the manual driving force T isdecreasing, then the electronic control unit 32 proceeds to step S39. Instep S39, the electronic control unit 32 calculates the correcteddriving force TX based on the second map, the inclination angle D, thecrank rotation speed N, and the manual driving force T and then proceedsto step S35. In step S35, the electronic control unit 32 calculates themotor output TM based on the calculated corrected driving force TX andproceeds to step S36. In step S36, the electronic control unit 32controls the motor 22 based on the motor output TM and then executes theprocessing from step S31 again after a predetermined cycle.

If the electronic control unit 32 determines in step S38 that the manualdriving force T is increasing, then the electronic control unit 32proceeds to step S40. In step S40, the electronic control unit 32calculates the corrected driving force TX based on the fourth map, theinclination angle D, and the manual driving force T and then proceeds tostep S35. More specifically, the electronic control unit 32 calculatesthe corrected driving force TX by adding the corrected value CX, whichis set in the fourth map, to the increasing speed of the manual drivingforce T or multiplying the increasing speed of the manual driving forceT by the corrected value CX, which is set in the fourth map. In stepS35, the electronic control unit 32 calculates the motor output TM basedon the calculated corrected driving force TX and then proceeds to stepS36. In step S36, the electronic control unit 32 controls the motor 22based on the motor output TM and then executes the processing from stepS31 again after a predetermined cycle.

Referring to FIG. 8, one example of the motor control in a case in whichthe first mode is selected will now be described. Timing chart A of FIG.8 shows the relationship of time and the manual driving force T. Timingchart B of FIG. 8 shows the relationship of time and the pitch angle DA.Timing chart C of FIG. 8 shows the relationship of time and the motoroutput TM. The timing charts A to C of FIG. 8 show a state in which thebicycle 10 is travelling with the crank rotation speed N kept constant.The solid line in the timing chart C of FIG. 8 shows the motor output TMin a case in which the inclination angle D changes while travelling. Thedouble-dashed line in the timing chart C of FIG. 8 shows the motoroutput TM in a case in which the inclination angle D does not changewhile travelling.

In the period from time t30 to t31 in the timing charts A to C of FIG.8, the pitch angle DA is greater than or equal to a first pitch angleDA1. In the period from time t30 to time t31, during period X1 in whichthe corrected driving force TX decreases, the manual driving force T andthe motor output TM change in the same manner as from time t11 to timet12 in the timing charts A to C of FIG. 5. In the period from time t30to time t31, during period X2 in which the corrected driving force TXincreases, that is, the crank arms 12 (refer to FIG. 1) are rotated fromthe top dead center or the bottom dead center to an intermediate anglebetween the top dead center and the bottom dead center, the motor outputTM is changed at an increase rate that is greater than the increase rateof the manual driving force T.

Time t31 is the time at which the pitch angle DA becomes less than orequal to the first pitch angle DA1 and greater than the second pitchangle DA2. In the period from time t31 to time t32, during period X1 inwhich the corrected driving force TX decreases, the manual driving forceT and the motor output TM change in a manner similar to time t11 to timet12 in the timing charts A and C of FIG. 5. In the period from time t31to time t32, during period X2 in which the corrected driving force TXincreases, the electronic control unit 32 decreases the response speed Qin accordance with the pitch angle DA. The increase rate of thecorrected driving force TX is less than that of the period from time t30to time t31.

Time t32 is the time at which the pitch angle DA becomes less than orequal to the second pitch angle DA2 but greater than the third pitchangle DA3. From time t32, during period X1 in which the correcteddriving force TX decreases, the manual driving force T and the motoroutput TM change in a manner similar to from time t12 in timing charts Aand C of FIG. 5. From time t32, during period X2 in which the correcteddriving force TX increases, the electronic control unit 32 decreases theresponse speed Q in accordance with the pitch angle DA. Thus, theincrease rate of the corrected driving force TX becomes less than thatof the period from time t31 to time t32.

Referring to FIG. 9, one example of the motor control in a case in whichthe second mode is selected will now be described. Timing chart A ofFIG. 9 shows the relationship of time and the manual driving force T.Timing chart B of FIG. 9 shows the relationship of time and the pitchangle DA. Timing chart C of FIG. 9 shows the relationship of time andthe motor output TM. The timing charts A to C of FIG. 9 show a state inwhich the bicycle 10 is travelling with the crank rotation speed N keptconstant. The solid line in the timing chart C of FIG. 9 shows oneexample of the execution of the motor control in a case in which theinclination angle D changes while travelling. The double-dashed line inthe timing chart C of FIG. 9 shows one example of the motor control in acase in which the inclination angle D does not change while travelling.

In the period from time t40 to t41 in the timing charts A to C of FIG.9, the pitch angle DA becomes less than or equal to the sixth pitchangle DA6 but greater than the fifth pitch angle DA5. In the period fromtime t40 to time t41, during period X1 in which the corrected drivingforce TX decreases, the manual driving force T and the motor output TMchange in the same manner as from time t21 to time t22 in the timingcharts A to C of FIG. 6. In the period from time t40 to time t41, duringperiod X2 in which the corrected driving force TX increases, that is,the crank arms 12 (refer to FIG. 1) are rotated from the top dead centeror the bottom dead center to an intermediate angle between the top deadcenter and the bottom dead center, the motor output TM is changed at anincrease rate that is greater than the increase rate of the manualdriving force T.

Time t41 is the time at which the pitch angle DA becomes less than orequal to the fifth pitch angle DA5 but greater than the fourth pitchangle DA4. In the period from time t41 to time t42, during period X1 inwhich the corrected driving force TX decreases, the manual driving forceT and the motor output TM change in a manner similar to time t21 to timet22 in the timing charts A and C of FIG. 6. In the period from time t41to time t42, during period X2 in which the corrected driving force TXincreases, the electronic control unit 32 decreases the response speed Qin accordance with the pitch angle DA. The increase rate of thecorrected driving force TX during period X2 is less than that of thecorrected driving force TX period from time t40 to time t41.

Time t42 is the time at which the pitch angle DA becomes less than orequal to the fourth pitch angle DA4. From time t42, during period X1 inwhich the corrected driving force TX decreases, the manual driving forceT and the motor output TM change in a manner similar to from time t22 intiming charts A to C of FIG. 6. From time t42, during period X2 in whichthe corrected driving force TX increases, the electronic control unit 32decreases the response speed Q in accordance with the pitch angle DA.Thus, the increase rate of the corrected driving force TX becomes lessthan that of the period from time t41 to time t42.

Third Embodiment

A third embodiment of the bicycle controller 30 will now be describedwith reference to FIGS. 1, 10, and 11. The third embodiment of thebicycle controller 30 is similar to the first embodiment of the bicyclecontroller 30 except in that a control is executed to change theresponse speed Q in accordance with the vehicle speed V and theinclination angle D. Same reference numerals are given to thosecomponents that are the same as the corresponding components of thefirst embodiment. Such components will not be described in detail.

In the present embodiment, the electronic control unit 32 shown in FIG.1 sets the response speeds R and Q for cases in which the vehicle speedV of the bicycle 10 is less than or equal to a first speed V1 to bedifferent from the response speeds R and Q for cases in which thevehicle speed V of the bicycle 10 exceeds the first speed V1.Preferably, the first speed V1 is set at the vehicle speed V that allowsfor determination that the bicycle 10 has started to travel. Preferably,the first speed V1 is set in a range from 1 to 10 km/h. In one example,the first speed V1 is set to 3 km/h. Preferably, the first speed V1 isstored beforehand in the memory 34. The memory 34 is configured so thatthe first speed V1 can be changed. For example, operation of theoperation unit 14 or use of an external device changes the first speedV1 stored in the memory 34. The electronic control unit 32 sets theresponse speed Q for a case in which the vehicle speed V of the bicycle10 is less than or equal to the first speed V1 to be higher than theresponse speed Q for a case in which the vehicle speed V of the bicycle10 exceeds the first speed V1. Further, the electronic control unit 32sets the response speed R for a case in which the vehicle speed V of thebicycle 10 is less than or equal to the first speed V1 to be lower thanthe response speed R for a case in which the vehicle speed V of thebicycle 10 exceeds the first speed V1.

The electronic control unit 32 sets the response speeds R and Q for acase during a predetermined period PX1 from the time at which thebicycle 10 starts to travel to be different from the response speeds Rand Q for a case in which the predetermined period PX1 has elapsed.Preferably, the predetermined period PX1 is set in the range of one toten seconds. In one example, the predetermined period PX1 is set tothree seconds. Preferably, the predetermined period PX1 is storedbeforehand in the memory 34. The memory 34 is configured to allow thepredetermined period PX1 to be changed. For example, operation of theoperation unit 14 or use of an external device changes the predeterminedperiod PX1 stored in the memory 34. The electronic control unit 32 setsthe response speed Q for a case during the predetermined period PX1 fromthe time at which the bicycle 10 starts to travel to be higher than theresponse speed Q for a case in which the predetermined period PX1 haselapsed. The electronic control unit 32 sets the response speed R for acase during the predetermined period PX1 from the time at which thebicycle 10 starts to travel to be lower than the response speed R for acase in which the predetermined period PX1 has elapsed.

If the inclination angle D on an uphill increases, then the electroniccontrol unit 32 decreases the response speed R in a case in which themanual driving force T decreases and increases the response speed Q in acase in which the manual driving force T increases. More specifically,on an uphill in which the pitch angle DA is greater than a firstpredetermined angle DX1, the electronic control unit 32 increases theresponse speed Q if the manual driving force T increases. The firstpredetermined angle DX1 is set to a positive value, in one example, ninedegrees.

If the inclination angle D on a downhill increases, then the electroniccontrol unit 32 increases the response speed R for a case in which themanual driving force T decreases and decreases the response speed Q fora case in which the manual driving force T increases. More specifically,on a downhill in which the pitch angle DA is less than a secondpredetermined angle D2, the electronic control unit 32 increases theresponse speed Q for a case in which the manual driving force Tincreases. The second predetermined angle D2 is set to a negative value,in one example, minus nine degrees.

With reference to FIGS. 10 to 12, a motor control that changes theresponse speeds R and Q in accordance with the inclination angle D ofthe vehicle speed V will now be described. The motor control is repeatedin predetermined cycles as long as the electronic control unit 32 issupplied with power.

In step S41, the electronic control unit 32 determines whether or notthe vehicle speed V is less than or equal to the first speed V1. If theelectronic control unit 32 determines that the vehicle speed V is lessthan or equal to the first speed V1, then the electronic control unit 32proceeds to step S42. In step S42, the electronic control unit 32determines whether or not the pitch angle DA is greater than the firstpredetermined angle DX1. If the electronic control unit 32 determinesthat the pitch angle DA is greater than the first predetermined angleDX1, then the electronic control unit 32 proceeds to step S43. In stepS43, the electronic control unit 32 decreases the response speed R andincreases the response speed Q. Then, the electronic control unit 32proceeds to step S44. For example, the electronic control unit 32decreases the response speed R to a value lower than an initial value RXof the response speed R that is stored beforehand in the memory 34, andthe electronic control unit 32 increases the response speed Q to a valuehigher than an initial value QX of the response speed Q that is storedbeforehand in the memory 34. Preferably, the initial values QX and RX ofthe response speeds Q and R are set to values that are suitable fortraveling on an even road in a case in which the vehicle speed V isgreater than the first speed V1.

In step S44, the electronic control unit 32 determines whether or notthe predetermined period PX1 has elapsed. For example, if the elapsedtime from the time at which the vehicle speed V was determined in stepS41 as being less than or equal to the first speed V1 becomes greaterthan or equal to the predetermined period PX1, then the electroniccontrol unit 32 determines that the predetermined period PX1 haselapsed. The electronic control unit 32 repeats the determination ofstep S44 until the predetermined period PX1 elapses. Preferably, thepredetermined period PX1 is set in a range of one to ten seconds. In oneexample, the predetermined period PX1 is set to three seconds. If thepredetermined period PX1 elapses, then the electronic control unit 32proceeds to step S45. In step S45, the electronic control unit 32returns the response speed R and the response speed Q to their originalvalues. The process of step S45 sets the response speed R and theresponse speed Q to the response speed R and the response speed Q priorto the change in step S43. For example, the electronic control unit 32returns the response speed R and the response speed Q to the initialvalues QX and RX stored in the memory 34.

If the electronic control unit 32 determines in step S42 that the pitchangle DA is not greater than the first predetermined angle DX1, then theelectronic control unit 32 proceeds to step S46. In step S46, theelectronic control unit 32 determines whether or not the pitch angle DAis less than the second predetermined angle D2. If the electroniccontrol unit 32 determines that the pitch angle DA is greater than orequal to the second predetermined angle D2, then the electronic controlunit 32 ends the processing. Thus, in a case in which the bicycle 10 ison a road in which the pitch angle DA is less than or equal to the firstpredetermined angle DX1 and greater than or equal to the secondpredetermined angle D2, the electronic control unit 32 ends theprocessing without changing the response speeds R and Q.

If the electronic control unit 32 determines that the pitch angle DA isless than the second predetermined angle D2 in step S46, then theelectronic control unit 32 proceeds to step S47. In step S47, theelectronic control unit 32 increases the response speed R and decreasesthe response speed Q. Then, the electronic control unit 32 proceeds tostep S44. For example, the electronic control unit 32 increases theresponse speed R to a value higher than the initial value RX of theresponse speed R that is stored beforehand in the memory 34 anddecreases the response speed Q to a value lower than the initial valueQX of the response speed Q that is stored beforehand in the memory 34.If the electronic control unit 32 determines in step S46 that the pitchangle DA is less than the second predetermined angle D2, then theelectronic control unit 32 increases the response speed R and lowers theresponse speed Q in step S47. Then, the electronic control unit 32proceeds to step S44.

In step S44, the electronic control unit 32 determines whether or notthe predetermined period PX1 has elapsed. For example, the electroniccontrol unit 32 determines that the predetermined period PX1 has elapsedin a case in which the elapsed period from the time at which theelectronic control unit 32 determines in step S41 that the vehicle speedV has become less than or equal to the first speed V1 becomes greaterthan or equal to the predetermined period PX1. The electronic controlunit 32 repeats the determination of step S44 until the predeterminedperiod PX1 elapses. If the predetermined period PX1 has elapsed, thenthe electronic control unit 32 proceeds to step S45. In step S45, theelectronic control unit 32 returns the response speed R and the responsespeed Q to their original values. The process of step S45 sets theresponse speed R and the response speed Q to the response speed R andthe response speed Q prior to the change in step S47. For example, theelectronic control unit 32 returns the response speed R and the responsespeed Q to the initial values QX and RX stored in the memory 34.

If the electronic control unit 32 determines in step S41 that thevehicle speed V is greater than the first speed V1, then the electroniccontrol unit 32 proceeds to step S48. In step S48, the electroniccontrol unit 32 determines whether or not the pitch angle DA is greaterthan the first predetermined angle DX1. If the electronic control unit32 determines that the pitch angle DA is greater than the firstpredetermined angle DX1, then the electronic control unit 32 proceeds tostep S49. In step S49, the electronic control unit 32 decreases theresponse speed R and increases the response speed Q. Then, theelectronic control unit 32 proceeds to step S50. For example, theelectronic control unit 32 decreases the response speed R to a valuelower than the initial value RX of the response speed R that is storedbeforehand in the memory 34, and the electronic control unit 32increases the response speed Q to a value higher than the initial valueQX of the response speed Q that is stored beforehand in the memory 34.The electronic control unit 32 sets the response speed R and theresponse speed Q to values differing from those set in step S43. Forexample, the response speed R set in step S43 by the electronic controlunit 32 is lower than the response speed R set in step S49, and theresponse speed Q set in step S43 by the electronic control unit 32 ishigher than the response speed Q set in step S49.

In step S50, the electronic control unit 32 determines whether or not apredetermined period PX2 has elapsed. More specifically, the electroniccontrol unit 32 determines that the predetermined period PX2 has elapsedin a case in which the elapsed period from the time at which theelectronic control unit 32 changes the response speeds R and Q in stepS49 becomes greater than or equal to the predetermined period PX2.Preferably, the predetermined period PX2 is set in a range of one to tenseconds. In one example, the predetermined period PX2 is set to threeseconds. Preferably, the predetermined period PX2 is stored beforehandin the memory 34. The memory 34 is configured to allow the predeterminedperiod PX2 to be changed. For example, operation of the operation unit14 or use of an external device changes the predetermined period PX2stored in the memory 34. The electronic control unit 32 repeats thedetermination of step S50 until the predetermined period PX2 elapses. Ifthe predetermined period PX2 elapses, then the electronic control unit32 proceeds to step S51. In step S51, the electronic control unit 32returns the response speed R and the response speed Q to their originalvalues. The process of step S51 sets the response speed R and theresponse speed Q to the response speed R and the response speed Q priorto the change in step S49. For example, the electronic control unit 32returns the response speed R and the response speed Q to the initialvalues QX and RX stored in the memory 34.

If the electronic control unit 32 determines in step S48 that the pitchangle DA is not greater than the first predetermined angle DX1, then theelectronic control unit 32 proceeds to step S52. In step S52, theelectronic control unit 32 determines whether or not the pitch angle DAis less than the second predetermined angle D2. If the electroniccontrol unit 32 determines that the pitch angle DA is greater than orequal to the second predetermined angle D2, then the electronic controlunit 32 ends the processing. Thus, in a case in which the bicycle 10 ison a road in which the pitch angle DA is less than or equal to the firstpredetermined angle DX1 and greater than or equal to the secondpredetermined angle D2, the electronic control unit 32 ends theprocessing without changing the response speeds R and Q.

If the electronic control unit 32 determines that the pitch angle DA isless than the second predetermined angle D2 in step S52, then theelectronic control unit 32 proceeds to step S53. In step S53, theelectronic control unit 32 increases the response speed R and decreasesthe response speed Q. Then, the electronic control unit 32 proceeds tostep S50. For example, the electronic control unit 32 increases theresponse speed R to a value higher than the initial value RX of theresponse speed R that is stored beforehand in the memory 34 anddecreases the response speed Q to a value lower than the initial valueQX of the response speed Q that is stored beforehand in the memory 34.For example, the response speed R set in step S53 by the electroniccontrol unit 32 is higher than the response speed R set in step S49, andthe response speed Q set in step S53 by the electronic control unit 32is lower than the response speed Q set in step S49.

In step S50, the electronic control unit 32 determines whether or notthe predetermined period PX2 has elapsed. More specifically, theelectronic control unit 32 determines that the predetermined period PX2has elapsed if the elapsed time from the time at which the responsespeeds R and Q are changed in step S53 becomes greater than or equal tothe predetermined period PX2. The electronic control unit 32 repeats thedetermination of step S50 until the predetermined period PX2 elapses. Ifthe predetermined period PX2 elapses, then the electronic control unit32 proceeds to step SM.

Fourth Embodiment

With reference to FIGS. 1, 12, and 13, a fourth embodiment of thebicycle controller 30 will now be described. The fourth embodiment ofthe bicycle controller 30 is similar to the first embodiment of thebicycle controller 30 except in that a control is executed to change theoutput torque TA of the motor 22 in accordance with the inclinationangle D. Same reference numerals are given to those components that arethe same as the corresponding components of the first embodiment. Suchcomponents will not be described in detail.

In the present embodiment, the electronic control unit 32 shown in FIG.1 is configured to control the motor 22 in accordance with the manualdriving force T in a riding mode. Further, the electronic control unit32 controls the motor 22 in accordance with the manual driving force T.In the riding mode, the electronic control unit 32 controls the outputtorque TA of the motor 22 so that the output torque TA is less than orequal to a predetermined torque TY. The predetermined torque TY ischanged in accordance with the inclination angle D of the bicycle 10.The predetermined torque TY includes a first torque TY1. The firsttorque TY1 is set in accordance with the output characteristics of themotor 22. Further, the first torque TY1 is set to a value that is lessthan the upper limit torque of the output torque TA of the motor 22 andin the proximity of the upper limit torque.

In a case in which the electronic control unit 32 controls the motor 22in accordance with the manual driving force T, the electronic controlunit 32 controls the output torque TA of the motor 22 so that the outputtorque TA is less than or equal to the first torque TY1. The firsttorque TY1 is changed in accordance with the inclination angle D of thebicycle 10. The memory 34 stores a fifth map that sets the relationshipof the first torque TY1 and the crank rotation speed N. The solid lineL31 in FIG. 12 shows one example of the fifth map. Preferably, the firsttorque TY1 is set for each riding mode. If the inclination angle D ofthe bicycle 10 increases on an uphill, then the electronic control unit32 increases the first torque TY1. If the inclination angle D of thebicycle 10 increases on a downhill, then the electronic control unit 32decreases the first torque TY1.

With reference to FIG. 13, motor control that changes the first torqueTY1 in accordance with the inclination angle D will now be described.The motor control is repeated in predetermined cycles as long as theelectronic control unit 32 is supplied with power.

In step S61, the electronic control unit 32 determines whether or notthe pitch angle DA is greater than the first predetermined angle DX1. Ifthe electronic control unit 32 determines that the pitch angle DA isgreater than the first predetermined angle DX1, then the electroniccontrol unit 32 proceeds to step S62. In step S62, the electroniccontrol unit 32 increases the first torque TY1 and then proceeds to stepS63. More specifically, the electronic control unit 32 switches thecontrol of the motor 22 from a control that uses the map shown by thesolid line L31 in FIG. 12 setting the relationship of the first torqueTY1 and the crank rotation speed N to a control that uses the map shownby the broken line L32 in FIG. 12 setting the relationship of the firsttorque TY1 and the crank rotation speed N.

In step S63, the electronic control unit 32 determines whether or notthe pitch angle DA is greater than the first predetermined angle DX1. Aslong as the electronic control unit 32 determines in step S63 that thepitch angle DA is greater than the first predetermined angle DX1, theelectronic control unit 32 repeats the determination of step S63. If theelectronic control unit 32 determines in step S63 that the pitch angleDA is less than or equal to the first predetermined angle DX1, then theelectronic control unit 32 proceeds to step S64 and returns the firsttorque TY1 to its original value. More specifically, the electroniccontrol unit 32 switches the control of the motor 22 using the mapsetting the relationship of the first torque TY1 and the crank rotationspeed N to the control executed prior to the switching in step S62.

If the electronic control unit 32 determines in step S61 that the pitchangle DA is less than or equal to the first predetermined angle DX1,then the electronic control unit 32 proceeds to step S65. In step S65,the electronic control unit 32 determines whether or not the pitch angleDA is less than the second predetermined angle D2. If the electroniccontrol unit 32 determines that the pitch angle DA is less than thesecond predetermined angle D2, then the electronic control unit 32proceeds to step S66. In step S66, the electronic control unit 32decreases the first torque TY1 and proceeds to step S67. Morespecifically, the electronic control unit 32 switches the control of themotor 22 from a control that uses the map shown by the solid line L31 inFIG. 12 setting the relationship of the first torque TY1 and the crankrotation speed N to a control that uses the map shown by thesingle-dashed line L32 in FIG. 12 setting the relationship of the firsttorque TY1 and the crank rotation speed N.

In step S67, the electronic control unit 32 determines whether or notthe pitch angle DA is less than the second predetermined angle D2. Aslong as the electronic control unit 32 determines in step S67 that thepitch angle DA is less than the second predetermined angle D2, theelectronic control unit 32 repeats the determination of step S67. If theelectronic control unit 32 determines in step S67 that the pitch angleDA is greater than or equal to the second predetermined angle D2, thenthe electronic control unit 32 proceeds to step S64 and returns thefirst torque TY1 to its original value. More specifically, theelectronic control unit 32 switches the control of the motor 22 usingthe map setting the relationship of the first torque TY1 and the crankrotation speed N to the control executed prior to the switching in stepS66.

If there are multiple riding modes, in which the ratio of the motoroutput TM to the manual driving force T differs for each riding mode,and the electronic control unit 32 increases the first torque TY1 instep S62, then the electronic control unit 32 preferably sets the firsttorque TY1 to the maximum torque of the motor output TM in the ridingmode in which the ratio of the motor output TM to the manual drivingforce T is the largest. If there are multiple riding modes, in which theratio of the motor output TM to the manual driving force T differs foreach riding mode, and the electronic control unit 32 decreases the firsttorque TY1 in step S66, then the electronic control unit 32 preferablysets the first torque TY1 to the maximum torque of the motor output TMin the riding mode in which the ratio of the motor output TM to themanual driving force T is the smallest.

Fifth Embodiment

With reference to FIGS. 1, and 14 to 16, a fifth embodiment of thebicycle controller 30 will now be described. The fifth embodiment of thebicycle controller 30 is similar to the first embodiment of the bicyclecontroller 30 except in that a control is executed to drive the motor 22in accordance with the operation of the operation unit 14. Samereference numerals are given to those components that are the same asthe corresponding components of the first embodiment. Such componentswill not be described in detail.

In the present embodiment, the electronic control unit 32 is configuredto switch between a riding mode and a walk mode in accordance withoperation of the operation unit 14 shown in FIG. 1. The electroniccontrol unit 32 controls the motor 22 in accordance with the operationof the operation unit 14. More specifically, in a case in which theoperation unit 14 is operated to drive the motor 22 in the walk mode,the electronic control unit 32 starts driving the motor 22 if the manualdriving force T is zero. In a case in which the electronic control unit32 controls the motor 22 in accordance with the operation of theoperation unit 14, the electronic control unit 32 controls the outputtorque TA of the motor 22 to be less than or equal to a second torqueTY2. In a case in which the electronic control unit 32 controls themotor 22 in accordance with operation of the operation unit 14, theelectronic control unit 32 controls the vehicle speed V to be less thanor equal to a predetermined vehicle speed V. The electronic control unit32 changes the increasing speed of the output torque TA of the motor 22in accordance with the inclination angle D of the bicycle 10. If theinclination angle D of the bicycle 10 increases on an uphill, then theelectronic control unit 32 increases the increasing speed of the outputtorque TA of the motor 22. If the inclination angle D of the bicycle 10increases on a downhill, then the electronic control unit 32 decreasesthe increasing speed of the output torque TA of the motor 22.

With reference to FIGS. 14 to 16, the motor control in the walk modewill now be described. The motor control is repeated in predeterminedcycles as long as the electronic control unit 32 is supplied with power.

In step S71, the electronic control unit 32 determines whether or notthere is a start request for driving the motor 22 in the walk mode. Morespecifically, if the operation unit 14 is operated to drive the motor 22in the walk mode and the manual driving force T is zero, then theelectronic control unit 32 determines that there is a start request fordriving the motor 22 in the walk mode. If the electronic control unit 32determines that there is no start request for driving the motor 22 inthe walk mode, then the electronic control unit 32 ends the processing.

If the electronic control unit 32 determines that there is a startrequest for driving the motor 22 in the walk mode, then the electroniccontrol unit 32 proceeds to step S72. In step S72, the electroniccontrol unit 32 determines whether or not the pitch angle DA is greaterthan the first predetermined angle DX1. If the electronic control unit32 determines that the pitch angle DA is greater than the firstpredetermined angle DX1, then the electronic control unit 32 proceeds tostep S73. In step S73, the electronic control unit 32 sets theincreasing speed of the output torque TA to the first increasing speedand then proceeds to step S77.

If the electronic control unit 32 determines in step S72 that the pitchangle DA is less than or equal to the first predetermined angle DX1,then the electronic control unit 32 proceeds to step S74. In step S74,then the electronic control unit 32 determines whether or not the pitchangle DA is less than the second predetermined angle D2. If theelectronic control unit 32 determines that the pitch angle DA is lessthan the second predetermined angle D2, then the electronic control unit32 proceeds to step S75. In step S75, the electronic control unit 32sets the increasing speed of the output torque TA to the secondincreasing speed and then proceeds to step S77.

If the electronic control unit 32 determines in step S74 that the pitchangle DA is greater than or equal to the second predetermined angle D2,then the electronic control unit 32 proceeds to step S76. In step S76,the electronic control unit 32 sets the increasing speed of the outputtorque TA to a third increasing speed and then proceeds to step S77. InFIG. 16, the broken line L41 shows the output torque TA in a case inwhich the first increasing speed is set. The single-dashed line L42shows the output torque TA in a case in which the second increasingspeed is set. The solid line L43 shows the output torque TA in a case inwhich the third increasing speed is set. The first increasing speed ishigher than the third increasing speed. The second increasing speed islower than the third increasing speed.

In step S77, the electronic control unit 32 starts driving the motor 22at the increasing speed set in step S73, S75, or S76 and then proceedsto step S78. In step S78, the electronic control unit 32 determineswhether or not the output torque TA is greater than or equal to thesecond torque TY2. The electronic control unit 32 repeats thedetermination of step S78 until the output torque TA reaches the secondtorque TY2. The process of step S78 increases the output torque TA tothe second torque TY2 as shown in FIG. 16 by the broken line L41, thesingle-dashed line L42, or the solid line 43.

If the electronic control unit 32 determines that the output torque TAis greater than or equal to the second torque TY2, then the electroniccontrol unit 32 proceeds to step S79. In step S79, the electroniccontrol unit 32 starts controlling the motor 22 in accordance with thevehicle speed V and then proceeds to step S80. In step S80, theelectronic control unit 32 determines whether or not there is a drivetermination request for the motor 22 in the walk mode. The electroniccontrol unit 32 determines that there is a drive termination request forthe motor 22 in the walk mode in any of the cases in which the operationunit 14 is no longer operated to drive the motor 22 in the walk mode,the operation unit 14 is operated to switch to the riding mode, and themanual driving force T becomes greater than zero. The electronic controlunit 32 repeats the processes of steps S79 and S80 until determiningthat there is a drive termination request for the motor 22 in the walkmode. If the electronic control unit 32 determines that there is a drivetermination request for the motor 22 in the walk mode, then theelectronic control unit 32 in step S81 stops driving the motor 22 in thewalk mode and ends the processing.

Sixth Embodiment

Referring to FIG. 17, a sixth embodiment of the bicycle controller 30will now be described. The sixth embodiment of the bicycle controller 30is similar to the first embodiment of the bicycle controller 30 exceptin that a control is executed to change the response speeds R and Q asthe bicycle starts to travel. Same reference numerals are given to thosecomponents that are the same as the corresponding components of thefirst embodiment. Such components will not be described in detail.

In the present embodiment, the electronic control unit 32 sets theresponse speeds R and Q so that the response speeds R and Q for a caseduring a predetermined period PX from the time at which the bicycle 10starts to travel differs from the response speeds for a case in whichthe predetermined period PX has elapsed. In one example, thepredetermined period PX is set to three seconds. The electronic controlunit 32 sets the response speed Q for a case during the predeterminedperiod PX from the time at which the bicycle 10 starts to travel to behigher than the response speed Q for a case in which the predeterminedperiod PX has elapsed.

With reference to FIG. 17, motor control for changing the responsespeeds R and Q when the bicycle starts to travel will now be described.The motor control is repeated in predetermined cycles as long as theelectronic control unit 32 is supplied with power.

In step S91, the electronic control unit 32 determines whether or notthe bicycle 10 has started to travel. If the electronic control unit 32determines that the bicycle 10 has not started to travel, then theelectronic control unit 32 ends the processing. For example, theelectronic control unit 32 determines that the bicycle 10 has started totravel if the vehicle speed V of the bicycle 10 changes from zero togreater than zero. Otherwise, the electronic control unit 32 determinesthat the bicycle 10 has not started to travel. If the electronic controlunit 32 determines that the bicycle 10 has started to travel, then theelectronic control unit 32 proceeds to step S92. In step S92, theelectronic control unit 32 decreases the response speed R and increasesthe response speed Q. Then, the electronic control unit 32 proceeds tostep S93. More specifically, the electronic control unit 32 decreasesthe response speed R to a value lower than the initial value RX of theresponse speed R that is stored beforehand in the memory 34 andincreases the response speed Q to a value higher than the initial valueQX of the response speed Q that is stored beforehand in the memory 34.

In step S93, the electronic control unit 32 determines whether or notthe predetermined period PX has elapsed. For example, if the period fromthe time at which the electronic control unit 32 determined in step S91that the bicycle 10 has started to travel is greater than or equal tothe predetermined period PX, then the electronic control unit 32determines that the predetermined period PX has elapsed. The electroniccontrol unit 32 repeats the determination of step S93 until thepredetermined period PX elapses. If the electronic control unit 32determines that the predetermined period PX has elapsed, then theelectronic control unit 32 proceeds to step S94. In step S94, theelectronic control unit 32 returns the response speed R and the responsespeed Q to their original values and then ends the processing. Morespecifically, the electronic control unit 32 returns the response speedR and the response speed Q to the initial values RX and QX storedbeforehand in the memory 34.

Seventh Embodiment

Referring to FIGS. 1 and 18, a seventh embodiment of the bicyclecontroller 30 will now be described. The seventh embodiment of thebicycle controller 30 is similar to the first embodiment of the bicyclecontroller 30 except in that a control is executed to change theresponse speeds R and Q in accordance with the vehicle speed V. Samereference numerals are given to those components that are the same asthe corresponding components of the first embodiment. Such componentswill not be described in detail.

In the present embodiment, the electronic control unit 32 sets theresponse speeds R and Q so that the response speeds R and Q for a casein which the vehicle speed V of the bicycle 10 is less than or equal tothe first speed V1 differs from the response speeds R and Q for a casein which the vehicle speed V of the bicycle 10 exceeds the first speedV1. Preferably, the first speed V1 is set to the vehicle speed V thatallows for determination that the bicycle 10 has started to travel. Inone example, the first speed V1 is preferably set in the range from 1 to10 km/h. In one example, the first speed V1 is set to 3 km/h. Theelectronic control unit 32 sets the response speed Q for a case in whichthe vehicle speed V of the bicycle 10 is less than or equal to the firstspeed V1 to be higher than the response speed Q for a case in which thevehicle speed V of the bicycle 10 exceeds the first speed V1. Further,the electronic control unit 32 sets the response speed R for a case inwhich the vehicle speed V of the bicycle 10 is less than or equal to thefirst speed V1 to be lower than the response speed R for a case in whichthe vehicle speed V of the bicycle 10 exceeds the first speed V1.

Referring to FIG. 18, the motor control that changes the first torqueTY1 in accordance with the inclination angle D will now be described.The motor control is repeated in predetermined cycles as long as theelectronic control unit 32 is supplied with power.

In step S95, the electronic control unit 32 determines whether or notthe vehicle speed V is less than or equal to the first speed V1. If theelectronic control unit 32 determines that the vehicle speed V isgreater than the first speed V1, then the electronic control unit 32ends the processing. If the electronic control unit 32 determines thatthe vehicle speed V is less than or equal to the first speed V1, thenthe electronic control unit 32 proceeds to step S96. In step S96, theelectronic control unit 32 decreases the response speed R and increasesthe response speed Q. Then, the electronic control unit 32 proceeds tostep S97. More specifically, the electronic control unit 32 decreasesthe response speed R to a value lower than the initial value RX of theresponse speed R that is stored beforehand in the memory 34 andincreases the response speed Q to a value higher than the initial valueQX of the response speed Q that is stored beforehand in the memory 34.

In step S97, the electronic control unit 32 determines whether or notthe vehicle speed V is less than or equal to the first speed V1. Theelectronic control unit 32 repeats the determination of step S97 untilthe vehicle speed V becomes greater than the first speed V1. If theelectronic control unit 32 determines that the vehicle speed V isgreater than the first speed V1, then the electronic control unit 32proceeds to step S98 and returns the response speed R and the responsespeed Q to their original values. The electronic control unit 32 thenends the processing. More specifically, the electronic control unit 32returns the response speed R and the response speed Q to the initialvalues RX and QX stored beforehand in the memory 34.

Modified Examples

The present invention is not limited to the foregoing embodiment andvarious changes and modifications of its components can be made withoutdeparting from the scope of the present invention. Also, the componentsdisclosed in the embodiment can be assembled in any combination forembodying the present invention. For example, some of the components canbe omitted from all components disclosed in the embodiment. Further,several of the modified examples described below can be combined.

The motor control of FIG. 2 can be modified to the motor control shownin FIG. 19. In the motor control of FIG. 19, in step S11, the electroniccontrol unit 32 computes the manual driving force T and then proceeds tostep S13 without determining the riding mode. In step S13, theelectronic control unit 32 computes the corrected driving force TX basedon the first map, the inclination angle D, the crank rotation speed N,and the manual driving force T. Then, the electronic control unit 32proceeds to step S14. In this modified example, the bicycle controller30 functions in only one riding mode and stores only the first map. Thebicycle controller 30 does not store the second map.

The motor control of FIG. 2 can be modified to the motor control shownin FIG. 20. In the motor control of FIG. 20, in step S11, the electroniccontrol unit 32 computes the manual driving force T and then proceeds tostep S17 without determining the riding mode. In step S17, theelectronic control unit 32 computes the corrected driving force TX basedon the second map, the inclination angle D, the crank rotation speed N,and the manual driving force T. Then, the electronic control unit 32proceeds to step S14. In this modified example, the bicycle controller30 functions in only one riding mode and stores only the second map. Thebicycle controller 30 does not store the second map.

The motor control of FIG. 2 can be modified to the motor control shownin FIG. 21. Instead of correcting the manual driving force T, thecorrection unit 48 is configured to correct the motor output TM, whichis computed based on the manual driving force T by the outputcomputation unit 50. In the motor control of FIG. 21, in step S21, theelectronic control unit 32 computes the manual driving force T. In stepS22, the electronic control unit 32 multiplies the manual driving forceT by a predetermined value to compute the motor output TM. In step S23,the electronic control unit 32 determines whether or not the presentriding mode is the first mode. If the electronic control unit 32determines that the riding mode is the first mode, then the electroniccontrol unit 32 proceeds to step S24. In step S24, the electroniccontrol unit 32 computes a corrected output TD based on the first map,the inclination angle D, the crank rotation speed N, and the motoroutput TM. Then, the electronic control unit 32 proceeds to step S25. Ifthe electronic control unit 32 determines in step S23 that the presentriding mode is not the first mode, that is, the present mode is thesecond mode, then the electronic control unit 32 proceeds to step S27.In step S27, the electronic control unit 32 computes the correctedoutput TD based on the second map, the inclination angle D, the crankrotation speed N, and the motor output TM.

In step S25, the electronic control unit 32 determines whether or notthe manual driving force T is decreasing. If the electronic control unit32 determines in step S25 that the manual driving force T is decreasing,then the electronic control unit 32 proceeds to step S26 and controlsthe motor 22 based on the corrected output TD. Then, after apredetermined cycle, the electronic control unit 32 starts the processagain from step S21.

If the electronic control unit 32 determines in step S25 that the manualdriving force T is not decreasing, then the electronic control unit 32proceeds to step S28 and determines whether or not the motor output TMis greater than the corrected output TD. If the electronic control unit32 determines in step S28 that the motor output TM is greater than thecorrected output TD, then the electronic control unit 32 proceeds tostep S29 and controls the motor 22 based on the motor output TM. Then,after a predetermined cycle, the electronic control unit 32 starts theprocess again from step S21.

If the electronic control unit 32 determines in step S28 that the motoroutput TM is less than or equal to the corrected output TD, then theelectronic control unit 32 proceeds to step S26 and controls the motor22 based on the corrected output TD. Then, after a predetermined cycle,the electronic control unit 32 starts the process again from step S21.

In the first and second embodiments, the electronic control unit 32 canbe configured to change the response speed R in accordance with theinclination angle D regardless of the crank rotation speed N. Morespecifically, the electronic control unit 32 can set the time constant Kusing the first map and the second map that include only therelationship of the inclination angle D and the time constant K. Thatis, the electronic control unit 32 sets the time constant K inaccordance with the inclination angle D regardless of the crank rotationspeed N.

In the first and second embodiments, the electronic control unit 32 setsthe time constant K using the first map or the second map. Instead ofusing a map, the electronic control unit 32 can use a computationequation to set the time constant K. In this case, the memory 34 storescomputation equations corresponding to riding modes such as equations(1) and (2), which are described above.

In the first and second embodiments, in the first mode and the secondmode, the electronic control unit 32 changes the response speed R in astepped manner in accordance with the inclination angle D. However, theresponse speed R can be changed in a continuous manner in accordancewith the inclination angle D. In this case, for example, coefficientsA1, A2, and B, which are used in equations (1) and (2), are calculatedfrom functions that change in accordance with the inclination angle D.

In the first embodiment, if the manual driving force T increases on adownhill, then the electronic control unit 32 can decrease the responsespeed R as the inclination angle D of the downhill increases.

In the second embodiment, the increase rate of the manual driving forceT can be set to be lower than the increase rate of the manual drivingforce T in a case in which the response speed Q is set to the initialvalue QX. In this case, as the response speed Q increases from theinitial value QX, the increase rate of the manual driving force Tapproaches the increase rate of the corrected driving force TX. As theresponse speed Q decreases from the initial value QX, the increase rateof the corrected driving force TX is retarded from the increase rate ofthe manual driving force T. In this modified example, in a case in whichthe electronic control unit 32 increases the manual driving force T, theelectronic control unit 32 can change the response speed Q by changingthe time constant K instead of changing the response speed Q by addingthe corrected value CX to the manual driving force T or multiplying themanual driving force T by the corrected value CX. More specifically, thetime constant K corresponding to the initial value QX is set to a valuethat is greater than zero. In this case, for example, the increase rateof the motor output TM during period X2 from time t30 to time t31 in thetiming chart C of FIG. 8 becomes closer to the increase rate of themanual driving force T than the increase rate of the motor output TMduring period X2 from time t31 to time t32. Further, the increase rateof the motor output TM during period X2 from time t41 to time t42 in thetiming chart C of FIG. 9 becomes closer to the increase rate of themanual driving force T than the increase rate of the motor output TMduring period X2 from time t41 to time t42.

In the second embodiment, one of the first mode and the second mode canbe omitted. For example, in a case in which the second mode is omitted,in the motor control of FIG. 7, the electronic control unit 32 can omitsteps S32, S38, S39 and S40. In this case, after performing the processof step S31, the electronic control unit 32 proceeds to step S33. In acase in which the first mode is omitted, in the motor control of FIG. 7,the electronic control unit 32 can omit steps S32, S33, S34 and S37. Inthis case, after performing the process of step S31, the electroniccontrol unit 32 proceeds to step S38.

In the third embodiment, instead of performing the determination of stepS44, the electronic control unit 32 can determine whether or not thevehicle speed V is greater than or equal to a second speed V2. In oneexample, the second speed V2 is set to 15 km/h. The electronic controlunit 32 repeats the determination of step S44 until the vehicle speed Vbecomes greater than or equal to the second speed V2. If the vehiclespeed V becomes greater than or equal to the second speed V2, then theelectronic control unit 32 proceeds to step S45.

In the third embodiment, instead of the determination of step S50, theelectronic control unit 32 can determine whether or not the vehiclespeed V is greater than or equal to the second speed V2. If the vehiclespeed V becomes greater than or equal to the second speed V2, then theelectronic control unit 32 proceeds to step SM.

In the third embodiment, one of the response speed R and the responsespeed Q for a case during the predetermined period PX1 from the time atwhich the bicycle 10 starts to travel can be different from that for acase in which the predetermined period PX1 has elapsed. Morespecifically, in at least one of step S43 and step S47 in FIG. 10, theelectronic control unit 32 can change just one of the response speed Rand the response speed Q.

In the third embodiment, at least one of step S44 and step S50 can beomitted from the flowchart of FIGS. 10 and 11. In a case in which stepS44 is omitted, if the electronic control unit 32 performs step S43 orstep S47, then the electronic control unit 32 ends the processing. Inthis case, if the electronic control unit 32 determines in step S46 thatthe pitch angle DA is greater than or equal to the second predeterminedangle D2, then the electronic control unit 32 can proceed to step S45.In a case in which step S50 is omitted, if the electronic control unit32 performs step S49 or step S53, then the electronic control unit 32ends the processing. In this case, if the electronic control unit 32determines in step S52 that the pitch angle DA is greater than or equalto the second predetermined angle D2, then the electronic control unit32 can proceed to step S51.

In the third embodiment, the electronic control unit 32 can set theresponse speeds R and Q for a case in which the vehicle speed V of thebicycle 10 is less than or equal to the first speed V1 to be differentfrom the response speeds R and Q for a case in which the vehicle speed Vof the bicycle 10 exceeds the first speed V1.

In the third embodiment and its modified examples, steps S41 and S48 toS53 can be omitted from the flowchart of FIGS. 10 and 11.

In the third embodiment, if the electronic control unit 32 sets theresponse speeds R and Q for a case in which the vehicle speed V of thebicycle 10 is less than or equal to the first speed V1 to be differentfrom the response speeds R and Q for a case in which the vehicle speed Vof the bicycle 10 exceeds the first speed V1, then the electroniccontrol unit 32 can change and differ just one of the response speed Rand the response speed Q. For example, in steps S43 and S47 of FIG. 10,the electronic control unit 32 changes only one of the response speed Rand the response speed Q. In steps S49 and S53 of FIG. 11, theelectronic control unit 32 changes only one of the response speed R andthe response speed Q.

In the third embodiment and its modified examples, in a case in whichthe electronic control unit 32 changes the response speeds R and Q inaccordance with the pitch angle DA of the bicycle 10, the electroniccontrol unit 32 can change just one of the response speed R and theresponse speed Q. For example, in at least one of steps S43, S47, S49and S53 of FIGS. 10 and 11, only one of the response speed R and theresponse speed Q is changed.

In the third embodiment and its modified examples, step S46 and S47 canbe omitted from the flowchart of FIG. 10. In this case, if theelectronic control unit 32 determines in step S42 that the pitch angleDA is less than or equal to the first predetermined angle DX1, then theelectronic control unit 32 proceeds to step S44.

In the third embodiment and its modified examples, steps S42 and S43 canbe omitted from the flowchart of FIG. 10. In this case, if theelectronic control unit 32 determines in step S41 that the vehicle speedV is less than or equal to the first speed V1, then the electroniccontrol unit 32 proceeds to step S46.

In the third embodiment and its modified examples, steps S52 and S53 canbe omitted from the flowchart of FIG. 11. In this case, if theelectronic control unit 32 determines in step S48 that the pitch angleDA is less than or equal to the first predetermined angle DX1, then theelectronic control unit 32 proceeds to step S50.

In the third embodiment and its modified examples, steps S48 and S49 canbe omitted from the flowchart of FIG. 11. In this case, if theelectronic control unit 32 determines in step S41 that the vehicle speedV is greater than the first speed V1, then the electronic control unit32 proceeds to step S52.

In the third embodiment and its modified examples, the flowchart of FIG.10 can be ended in a case in which the process of step S47 ends.Further, the flowchart of FIGS. 10 and 11 can be ended in a case inwhich the process of step S53 ends.

In the fourth embodiment, steps S65, S66 and S67 can be omitted from theflowchart of FIG. 13. In this case, if the electronic control unit 32determines in step S61 that the pitch angle DA is less than or equal tothe first predetermined angle DX1, then the electronic control unit 32ends the processing.

In the fourth embodiment, steps S61, S62 and S63 can be omitted from theflowchart of FIG. 13. In this case, if the electronic control unit 32 issupplied with power, then the electronic control unit 32 performs theprocess of step S65.

In the fifth embodiment, steps S74 and S75 can be omitted from theflowchart of FIG. 14. In this case, if the electronic control unit 32determines in step S72 that the pitch angle DA is less than or equal tothe first predetermined angle DX1, then the electronic control unit 32proceeds to step S76.

In the fifth embodiment, step S72 and step S73 can be omitted from theflowchart of FIG. 14. In this case, if the electronic control unit 32determines in step S71 that there is a start request for driving themotor 22 in the walk mode, the electronic control unit 32 proceeds tostep S74.

In the fifth embodiment and its modified examples, the second torque TY2can be changed in accordance with the inclination angle D of the bicycle10. In one example, the electronic control unit 32 increases the secondtorque TY2 if the inclination angle of the bicycle 10 increases on anuphill. If the inclination angle D of the bicycle 10 increases on adownhill, then the electronic control unit 32 decreases the secondtorque TY2. For example, as shown in FIG. 22, the electronic controlunit 32 performs step S82 instead of step S73 of FIG. 14, step S83instead of step S75 of FIG. 14, and step S84 instead of step S76 of FIG.14. In step S82, the electronic control unit 32 sets the increasingspeed of the output torque TA to the first increasing speed and sets thesecond torque TY2 to a first value TZ1. In step S83, the electroniccontrol unit 32 sets the increasing speed of the output torque TA to thesecond increasing speed and sets the second torque TY2 to a second valueTZ2. In step S84, the electronic control unit 32 sets the increasingspeed of the output torque TA to the third increasing speed and sets thesecond torque TY2 to a third value TZ3. The first value TZ1 is greaterthan the third value TZ3. The second value TZ2 is less than the thirdvalue TZ3. Thus, if the pitch angle DA is greater than the firstpredetermined angle DX1, then the electronic control unit 32 controlsthe motor 22 to become less than or equal to the second torque TY2,which is greater than for a case in which the pitch angle DA is greaterthan or equal to the second predetermined angle D2 and less than orequal to the first predetermined angle DX1. If the pitch angle DA isless than the second predetermined angle D2, then the electronic controlunit 32 controls the motor 22 to become less than or equal to the secondtorque TY2, which is less than for a case in which the pitch angle DA isgreater than or equal to the second predetermined angle D2 and less thanor equal to the first predetermined angle DX1.

In the modified example shown in FIG. 22, the process for changing theoutput torque TA can be omitted in at least one of steps S82, S83, andS84. In this case, the increasing speed of the output torque TA isconstant regardless of the inclination angle D of the bicycle 10.

In the modified example shown in FIG. 22, steps S74 to S83 can beomitted from the flowchart. In this case, if the electronic control unit32 determines in step S72 that the pitch angle DA is less than or equalto the first predetermined angle DX1, then the electronic control unit32 proceeds to step S84.

In the modified example shown in FIG. 22, steps S72 and S82 can beomitted from the flowchart. In this case, if the electronic control unit32 determines that there is a start request for driving the motor 22 inthe walk mode, then the electronic control unit 32 proceeds to step S74.

In the fifth embodiment, the electronic control unit 32 can change theincreasing speed of the output torque TA of the motor 22 in accordancewith the change amount of the inclination angle D of the bicycle 10. Inone example, if the increasing speed of the inclination angle D of thebicycle 10 on an uphill increases, then the electronic control unit 32increases the increasing speed of the output torque TA of the motor 22.If the increasing speed of the inclination angle D of the bicycle 10 ona downhill increases, then the electronic control unit 32 decreases theincreasing speed of the output torque TA of the motor 22. For example,after the electronic control unit 32 sets the increasing speed of theoutput torque TA in step S73, S75 or step S76 of FIG. 14, the electroniccontrol unit 32 proceeds to step S85, which is shown in FIG. 23. In stepS85, the electronic control unit 32 determines whether or not the pitchangle DA has become greater than zero and whether or not the increasingspeed of the pitch angle DA has increased. If the electronic controlunit 32 determines that the pitch angle DA is greater than zero and thatthe increasing speed of the pitch angle DA has increased, then theelectronic control unit 32 proceeds to step S86. In step S86, theelectronic control unit 32 increases the increasing speed of the outputtorque TA and then proceeds to step S78. In a case in which theelectronic control unit 32 in step S85 gives at least one of adetermination that the pitch angle DA is less than or equal to zero anda determination that the increasing speed of the pitch angle DA has notincreased, the electronic control unit 32 proceeds to step S87. In stepS87, the electronic control unit 32 determines whether or not the pitchangle DA is less than zero and whether or not the decreasing speed ofthe pitch angle DA has increased. If the electronic control unit 32determines that the pitch angle DA is less than zero and that thedecreasing speed of the pitch angle DA has increased, then theelectronic control unit 32 proceeds to step S88. In step S88, theelectronic control unit 32 decreases the increasing speed of the outputtorque TA and proceeds to step S78. In step S78, the electronic controlunit 32 repeats the processes from step S85 until the output torque TAbecomes greater than or equal to the second torque TY2. If theelectronic control unit 32 determines in step S78 that the output torqueTA has become greater than or equal to the second torque TY2, then theelectronic control unit 32 proceeds to step S79. If the electroniccontrol unit 32 in step S87 gives at least one of a determination thatthe pitch angle DA is zero or greater and a determination that thedecreasing speed of the pitch angle DA has not increased, then theelectronic control unit 32 proceeds to step S78.

In the modified example shown in FIG. 23, steps S87 and S88 can beomitted from the flowchart. In this case, if the electronic control unit32 in step S85 gives at least one of a determination that the pitchangle DA is zero or less and a determination that the increasing speedof the pitch angle DA has not increased, then the electronic controlunit 32 proceeds to step S78.

In the modified example shown in FIG. 23, steps S85 and S86 can beomitted from the flowchart. In this case, the electronic control unit 32performs the process of step S77 and then proceeds to step S87.

In the sixth embodiment, the electronic control unit 32 does not have tochange the response speed R. More specifically, in step S92 of FIG. 17,the electronic control unit 32 changes the response speed Q but does notchange the response speed R.

In the sixth embodiment, the electronic control unit 32 can change theresponse speeds R and Q after the electronic control unit 32 is suppliedwith power and before the bicycle 10 starts to travel. For example, inthe flowchart of FIG. 17, step S91 and step S92 are reversed. In thiscase, if the bicycle 10 stops, then the electronic control unit 32 canperform the process of step S92. The electronic control unit 32 proceedsto step S91 as the bicycle 10 starts to travel. If the electroniccontrol unit 32 determines in step S91 that the bicycle 10 has startedto travel, then the electronic control unit 32 proceeds to step S93.

In the seventh embodiment, the electronic control unit 32 does not haveto change the response speed R. More specifically, in step S96 of FIG.18, the electronic control unit 32 changes the response speed Q but doesnot change the response speed R.

In the seventh embodiment, the electronic control unit 32 can change theresponse speeds R and Q after the electronic control unit 32 is suppliedwith power and before the vehicle speed V becomes greater than zero andless than or equal to the first speed V1. For example, in the flowchartof FIG. 18, step S95 and step S96 can be reversed. In this case, if thebicycle 10 stops, then the electronic control unit 32 can perform theprocess of step S96. If the electronic control unit 32 determines instep S95 that the vehicle speed V is less than or equal to the firstspeed V1, then the electronic control unit 32 proceeds to step S97.

The electronic control unit 32 can change the response speeds R and Q inaccordance with changes in the inclination angle D of the bicycle 10. Ina case in which the increasing speed of the inclination angle D of thebicycle 10 increases on an uphill, the electronic control unit 32increases the response speed Q if the manual driving force T increaseson an uphill. In a case in which the increasing speed of the inclinationangle D of the bicycle 10 increases on an uphill, the electronic controlunit 32 decreases the response speed R. For example, the electroniccontrol unit 32 executes the control shown in FIG. 24. In step S101, theelectronic control unit 32 determines whether or not the pitch angle DAis greater than zero and the increasing speed of the pitch angle DA hasincreased. If the electronic control unit 32 determines that the pitchangle DA is greater than zero and that the increasing speed of the pitchangle DA has increased, then the electronic control unit 32 proceeds tostep S102. In step S102, the electronic control unit 32 decreases theresponse speed R and increases the response speed Q. Then, theelectronic control unit 32 ends the processing. If the electroniccontrol unit 32 in step S101 gives at least one of a determination thatthe pitch angle DA is zero or less and a determination that theincreasing speed of the pitch angle DA has not increased, then theelectronic control unit 32 proceeds to step S103. In step S103, theelectronic control unit 32 determines whether or not the pitch angle DAis less than zero and whether or not the decreasing speed of the pitchangle DA has increased. If the electronic control unit 32 determinesthat the pitch angle DA is less than zero and that the decreasing speedof the pitch angle DA has increased, then the electronic control unit 32proceeds to step S104. In step S104, the electronic control unit 32increases the response speed R and decreases the response speed Q. Ifthe electronic control unit 32 in step S103 gives at least one of adetermination that the pitch angle DA is zero or greater and adetermination that the decreasing speed of the pitch angle DA is notincreasing, then the electronic control unit 32 ends the processingwithout changing the response speeds R and Q. In this modified example,after changing the response speeds R and Q in step S102 and step S104,the electronic control unit 32 can return the response speeds R and Q totheir original values after a predetermined period.

In the modified example shown in FIG. 24, step S103 and step S104 can beomitted from the flowchart. In this case, if the electronic control unit32 in step S101 gives at least one of a determination that the pitchangle DA is zero or less and a determination that the increasing speedof the pitch angle DA is not increasing, then the electronic controlunit 32 ends the processing.

In the modified example shown in FIG. 24, steps S101 and S102 can beomitted from the flowchart. In this case, the electronic control unit 32performs the process of step S103 if the electronic control unit 32 issupplied with power.

If the inclination angle D of the bicycle 10 changes from an anglecorresponding to an uphill to a third angle DX3 or greater thatcorresponds to a downhill during a first period, then the electroniccontrol unit 32 can decrease the response speed Q if the manual drivingforce T increases. If the inclination angle D of the bicycle 10 changesfrom an angle corresponding to an uphill to the third angle DX3 orgreater that corresponds to a downhill during the first period, then theelectronic control unit 32 can increase the response speed R.Preferably, the first period can be set to a range of one to tenseconds. In one example, the first period is set to three seconds.Preferably, the first period is stored beforehand in the memory 34. Thememory 34 is configured to allow the first period to be changed. Forexample, the operation of the operation unit 14 or the use of anexternal device changes the first period stored in the memory 34. Forexample, the electronic control unit 32 executes the control shown inFIG. 25. In step S105, the electronic control unit 32 determines whetheror not the pitch angle DA has changed from an angle greater than zero tothe third angle DX3 or less that is less than zero. If the electroniccontrol unit 32 determines that the pitch angle DA has changed from anangle greater than zero to the third angle DX3 or less that is less thanzero, then the electronic control unit 32 proceeds to step S106. In stepS106, the electronic control unit 32 increases the response speed R anddecreases the response speed Q. Then, the electronic control unit 32ends the processing. If the electronic control unit 32 determines instep S105 that the pitch angle DA has not changed from an angle greaterthan zero to the third angle DX3 or less that is less than zero, thenthe electronic control unit 32 ends the processing without changing theresponse speeds R and Q. In this modified example, after changing theresponse speeds R and Q in step S106, the electronic control unit 32 canreturn the response speeds R and Q to their original values after apredetermined period. In the flowchart of FIG. 25, the electroniccontrol unit 32 does not have to change the response speed R.

The electronic control unit 32 can obtain the inclination angle D usingthe Global Positioning System (GPS) and map information includingaltitude information. Further, the electronic control unit 32 caninclude an altitude sensor that detects the atmospheric pressure. Inthis case, the electronic control unit 32 can accurately obtain theinclination angle D using the output of the altitude sensor in additionto the GPS information. An inclination detector can include a GPSreceiver, a memory that stores map information, and an altitude sensor.Information of the inclination angle D obtained by the GPS can be inputto the electronic control unit 32, for example, via a cycle computer, asmartphone, or the like. The rider can also input the inclination angleD to the electronic control unit 32.

The low-pass filter 52 can be replaced by a moving average filter. Aslong as the response speed R of the motor 22 with respect to a change inthe manual driving force T can be changed, any structure can beemployed.

The electronic control unit 32 can compute the inclination angle D basedon the manual driving force T and the crank rotation speed N. In thiscase, for example, the electronic control unit 32 computes a large pitchangle DA if the manual driving force T is high and the crank rotationspeed N is low. More specifically, the electronic control unit 32determines that the inclination angle D on an uphill is large when themanual driving force T is high and the crank rotation speed N is low anddetermines that the inclination angle D on a downhill is large when themanual driving force T is low and the crank rotation speed N is high.Further, in this modified example, the inclination angle D can becomputed using the speed of the bicycle 10 in addition to the manualdriving force T and the crank rotation speed N.

The electronic control unit 32 can estimate the crank rotation speed Nusing the speed of the bicycle 10. For example, the electronic controlunit 32 can estimate the crank rotation speed N using the tire diameterand the gear ratio of the bicycle 10.

What is claimed is:
 1. A bicycle controller comprising: an electroniccontrol unit configured to control a motor, which assists propulsion ofa bicycle, in accordance with a manual driving force, the electroniccontrol unit being further configured to change a response speed of themotor with respect to a change in the manual driving force in accordancewith an inclination angle of the bicycle.
 2. The bicycle controlleraccording to claim 1, wherein the electronic control unit is furtherconfigured to change the response speed in a case in which the manualdriving force decreases.
 3. The bicycle controller according to claim 2,wherein the electronic control unit is further configured to decreasethe response speed in a case in which the inclination angle of thebicycle increases on an uphill.
 4. The bicycle controller according toclaim 2, wherein the electronic control unit is further configured toincrease the response speed in a case in which the inclination angle ofthe bicycle increases on a downhill.
 5. The bicycle controller accordingto claim 1, wherein the electronic control unit is further configured tochange the response speed in a case in which the manual driving forceincreases.
 6. The bicycle controller according to claim 5, wherein theelectronic control unit is further configured to increase the responsespeed in a case in which the inclination angle of the bicycle increaseson an uphill.
 7. The bicycle controller according to claim 5, whereinthe electronic control unit is further configured to decrease theresponse speed in a case in which the inclination angle of the bicycleincreases on a downhill.
 8. The bicycle controller according to claim 1,wherein the electronic control unit is further configured to change theresponse speed in a stepped manner in accordance with the inclinationangle of the bicycle.
 9. The bicycle controller according to claim 1,wherein the electronic control unit is further configured to fix theresponse speed in a case in which the inclination angle of the bicycleon an uphill is greater than or equal to a first angle.
 10. The bicyclecontroller according to claim 1, wherein the electronic control unit isfurther configured to fix the response speed in a case in which theinclination angle of the bicycle on a downhill is greater than or equalto a second angle.
 11. The bicycle controller according to claim 1,wherein the electronic control unit is further configured to set theresponse speed for a case in which a vehicle speed of the bicycle isless than or equal to a first speed to be different from the responsespeed for a case in which the vehicle speed of the bicycle exceeds thefirst speed.
 12. The bicycle controller according to claim 1, whereinthe electronic control unit is further configured to change the responsespeed in accordance with a change in the inclination angle of thebicycle.
 13. The bicycle controller according to claim 12, wherein upondetermining an increasing speed of the inclination angle of the bicycleincreases on an uphill, the electronic control unit is furtherconfigured to increase the response speed in a case in which the manualdriving force increases.
 14. The bicycle controller according to claim12, wherein upon determining the inclination angle of the bicyclechanges during a first period from an angle corresponding to an uphillto a third angle or greater on a downhill, the electronic control unitis further configured to decrease the response speed in a case in whichthe manual driving force increases.
 15. The bicycle controller accordingto claim 1, wherein the electronic control unit is further configured tochange the response speed in accordance with a rotation speed of a crankof the bicycle.
 16. The bicycle controller according to claim 15,wherein the electronic control unit is further configured to control themotor in a first mode that decreases the response speed as the rotationspeed of the crank increases.
 17. The bicycle controller according toclaim 16, wherein the electronic control unit is further configured tofix the response speed in the first mode in a case in which the rotationspeed of the crank is higher than or equal to a first speed.
 18. Thebicycle controller according to claim 15, wherein the electronic controlunit is further configured to control the motor in a second mode thatincreases the response speed as the rotation speed of the crankincreases.
 19. The bicycle controller according to claim 18, wherein theelectronic control unit is further configured to fix the response speedin the second mode in a case in which the rotation speed of the crank ishigher than or equal to a second speed.
 20. The bicycle controlleraccording to claim 16, wherein the electronic control unit is furtherconfigured to control the motor in a second mode that increases theresponse speed as the rotation speed of the crank increases.
 21. Thebicycle controller according to claim 20, wherein the electronic controlunit is further configured to fix the response speed in the second modein a case in which the rotation speed of the crank is higher than orequal to a second speed.
 22. The bicycle controller according to claim20, wherein the electronic control unit is further configured to switchbetween the first mode and the second mode in accordance with operationof an operation unit that is configured to communicate with theelectronic control unit.
 23. The bicycle controller according to claim1, wherein the electronic control unit is further configured to changethe response speed with a low-pass filter.
 24. A bicycle controllercomprising: an electronic control unit configured to control a motor,which assists propulsion of a bicycle, in accordance with operation ofan operation unit provided on the bicycle, the electronic control unitbeing configured to change an increasing speed of an output torque ofthe motor in accordance with at least one of an inclination angle of thebicycle and a change amount of the inclination angle of the bicycle. 25.The bicycle controller according to claim 24, wherein the electroniccontrol unit is further configured to increase the increasing speed ofthe output torque of the motor in a case in which the inclination angleof the bicycle increases on an uphill.
 26. The bicycle controlleraccording to claim 24, wherein the electronic control unit is furtherconfigured to decrease the increasing speed of the output torque of themotor in a case in which the inclination angle of the bicycle increaseson a downhill.
 27. The bicycle controller according to claim 24, whereinthe electronic control unit is further configured to increase theincreasing speed of the output torque of the motor in a case in which anincreasing speed of the inclination angle of the bicycle increases on anuphill.
 28. The bicycle controller according to claim 24, wherein theelectronic control unit is further configured to decrease the increasingspeed of the output torque of the motor in a case in which an increasingspeed of the inclination angle of the bicycle increases on a downhill.29. A bicycle controller comprising: an electronic control unitconfigured to control a motor that assists propulsion of a bicycle, theelectronic control unit being further configured to control an outputtorque of the motor to be less than or equal to a predetermined torque,and the predetermined torque is changed in accordance with aninclination angle of the bicycle.
 30. The bicycle controller accordingto claim 29, wherein the predetermined torque includes a first torque,the electronic control unit is further configured to control the motorin accordance with a manual driving force, the electronic control unitis further configured to control the output torque of the motor to beless than or equal to the first torque in a case in which the electroniccontrol unit controls the motor in accordance with the manual drivingforce, and the first torque is changed in accordance with theinclination angle of the bicycle.
 31. The bicycle controller accordingto claim 30, wherein the electronic control unit is further configuredto increase the first torque in a case in which the inclination angle ofthe bicycle increases on an uphill.
 32. The bicycle controller accordingto claim 29, wherein the predetermined torque includes a second torque,the electronic control unit is configured to control the motor inaccordance with operation of an operation unit provided on the bicycle,the electronic control unit is further configured to control the outputtorque of the motor to be less than or equal to the second torque in acase in which the electronic control unit controls the motor inaccordance with the operation of the operation unit, and the secondtorque is changed in accordance with the inclination angle of thebicycle.
 33. The bicycle controller according to claim 32, wherein theelectronic control unit is further configured to increase the secondtorque in a case in which the inclination angle of the bicycle increaseson an uphill.
 34. The bicycle controller according to claim 1, furthercomprising an inclination detector that detects the inclination angle ofthe bicycle.
 35. The bicycle controller according to claim 1, whereinthe electronic control unit is further configured to compute theinclination angle based on the manual driving force and a rotation speedof a crank of the bicycle.
 36. A bicycle controller comprising: anelectronic control unit configured to control a motor, which assistspropulsion of a bicycle, in accordance with a manual driving force, theelectronic control unit being further configured to sets a responsespeed of the motor with respect to a change in the manual driving forcefor a case in which a vehicle speed of the bicycle is less than or equalto a first speed to be different from the response speed for a case inwhich the vehicle speed of the bicycle exceeds the first speed.
 37. Thebicycle controller according to claim 36, wherein the electronic controlunit is further configured to set the response speed for the case inwhich the vehicle speed of the bicycle is less than or equal to thefirst speed to be higher than the response speed for the case in whichthe vehicle speed of the bicycle exceeds the first speed.
 38. A bicyclecontroller comprising: an electronic control unit configured to controla motor, which assists propulsion of a bicycle, in accordance with amanual driving force, the electronic control unit is further configuredto set a response speed of the motor with respect to a change in themanual driving force input to the bicycle for a case within apredetermined period from a time at which the bicycle starts to travelto be different from the response speed for a case in which thepredetermined period has elapsed.
 39. The bicycle controller accordingto claim 38, wherein the electronic control unit is further configuredto set the response speed for the case within the predetermined periodfrom the time at which the bicycle starts to travel to be higher thanthe response speed for the case in which the predetermined period haselapsed.